Date post: | 15-Aug-2015 |
Category: |
Technology |
Upload: | tu |
View: | 170 times |
Download: | 4 times |
Advanced Topics in IP Multicast Deployment BRKIPM-2008
Greg Shepherd
Distinguished Engineer
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Abstract Reminder
This session covers tools and techniques that will assist with deploying IP Multicast.
We begin with some configuration examples which discuss PIM modes and Rendezvous Point Deployment models for PIM SM domains
Examples are then given for ways of interconnecting separate PIM domains
A description of a technology called Automatic Multicast Tunnels (for extending multicast content between sites which are not homogeneously connected) is provided
We discuss the integration of multicast with MPLS (Label Switched Multicast).
We discuss ways of delivering a highly available multicast service.
We briefly discuss the deployment of IP Multicast in a wireless environment.
This session is primarily for network engineers in enterprise and service provider network environment. Attendees should have a basic understanding of IP Multicast
3
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multicast Market Overview
PIM Configuration notes
Interconnecting PIM domains
Label Switched Multicast
High Availability
Multicast in 802.11
4
Agenda
Multicast Overview
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multicast Applications
6
Finance (Trading, Market Data, Financial SP)
‒ Tibco, Hoot-n-Holler, Data Systems
Enterprise Video and collaborative environments
‒ Cisco TelePresence®, DMS, MP/WebEx
Video Conferencing, Video Surveillance
Broadband (Entertainment)
‒ Includes Cable, DSL, ETTH, LRE, Wireless
‒ Broadcast TV / IP/TV, VOD, Connected Home
Service Provider (Transit Services)
‒ Native v4 and v6
‒ Label Switched Multicast (LSM)
‒ Multicast VPNs (IP and MPLS-based)
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multicast Benefits For Content Delivery
Growth of Internet Based Live Video Services
7
By 2014 10% of all Internet video content will be live
PIM Configuration Notes
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multicast Application Types
9
Multicast Applications
One-to-Many (1toM) Many-to-Many (MtoM) Many-to-One (Mto1)
Audio/Video Lectures, presentations, concerts, television, radio
Push Media News headlines, weather updates, sports scores
Distribution Web site content, executable binaries
Announcements Network time, multicast session schedules, random numbers, keys, security
Monitoring Stock prices, sensors
Conferencing Audio/Video conferences, whiteboards
Sharing Resources Synchronized distributed databases
Games Multi-player with distributed interactive simulations
Others Concurrent processing, collaboration, two-way distance learning
Resource Discovery Service location, device discovery
Data Collection Monitoring applications, video surveillance
Others Auctions, polling, jukebox, accounting
For a detailed analysis see RFC3170
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
The Multicast “Application Spectrum”
10
Many-to-Many | Few applications One-to-Many applications
SSM For One-to-Many applications
Eliminates need for RP Engineering
Data and Control Planes decoupled
Bidir For Many-to-Many | Few applications
Drastically reduces (S,G) state in network
Data and Control Planes decoupled
All modes can coexist and applications can be moved gracefully (by group) between modes
SM For One-to-Many applications
Original (Classic)
Supports both Shared and Source Trees
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Impact of Source Specific Multicast (SSM)
Hosts join a specific source within a group
Content identified by specific (S,G) instead of (*,G)
Hosts responsible for learning (S,G) information
Last-hop router sends (S,G) join toward source
Shared Tree is never Joined or used
Eliminates possibility of content Jammers
Only specified (S,G) flow is delivered to host
Eliminates Networked-Based Source Discovery
No RPs for SSM groups
Simplifies address allocation
Content sources can use same group without fear of interfering with each other
11
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Socket Interface Extensions for Multicast
Protocol Independent (supports both IPv4 and IPv6)
Source-Specific Multicast API
– Section 5.1.2 of the RFC
– MCAST_JOIN_SOURCE_GROUP Join Source Specific Group
– MCAST_LEAVE_SOURCE_GROUP Leave Source Specific Group
– MCAST_LEAVE_GROUP Drop all sources for group / interface
Suggested best practices
– One multicast group per socket to prevent overload
– Verify interface presently used for multicast (Ethernet, Wi-Fi, 3G, etc..)
Source Filters (RFC 3678)
12
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Rendezvous Points Auto-RP
13
Dynamic way to learn RP to Group mapping information for IPv4
Two IANA reserved groups forward mapping information:
‒ 224.0.1.39 - cisco-rp-announce
‒ 224.0.1.40 - cisco-rp-discovery
Groups carry Group to RP mappings
Usually forwarded in Dense Mode:
‒ IOS state appear in mroute tables
‒ NXOS creates no visible mroutes / configured to forward / listen to groups:
‒ ip pim auto-rp forward listen
‒ IOS XR RPF floods to neighbors (no requirement for Dense Mode)
This helps when:
‒ RP address and group ranges change often
‒ Network has many routers
‒ Simple config desired
‒ Several RPs for different applications
‒ RPs maintained by different administrative groups
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Auto-RP Listener – Cisco IOS
14
Use global command (recommended):
‒ ip pim autorp listener
‒ Added support for Auto-RP Environments
‒ Modifies interface behavior:
Interface configured in SM and only use DM for Auto-RP group
Only needed if Auto-RP is used
Use with interface command
‒ ip pim sparse-mode
Prevents DM Flooding
No longer need:
‒ ip pim sparse-dense-mode
‒ Available 12.3(4)T, 12.2(28)S, 12.1(13)E7
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Avoid DM Fallback Automatically – Cisco IOS
IOS global command – no ip pim dm-fallback
Totally prevents DM Fallback!
– No DM Flooding (since all state remains in SM)
Default RP Address = 0.0.0.0 [nonexistent]
– Used if all RPs fail All SPTs remain active
Enabled by default if all interfaces are in sparse mode
Available 12.3(4)T, 12.2(33)SXH
15
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Auto-RP in IOS XR
IOS XR supports Auto-RP
IOS XR Auto RP operation is interoperable with IOS
IOS XR needs no DM state
Auto RP groups RPF flooded to PIM neighbors
No support for AutoRP in IPv6 in ANY OS
16
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Rendezvous Points - Anycast RP
Allows RP redundancy (even with static RP assignment)
Converges in (deterministic) IGP timescale
Relies on MSDP (IOS and IOS XR) or entirely based on PIM (NXOS)
http://tools.ietf.org/html/rfc3446
17
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Anycast RP – MDSP Config
18
Interface loopback 0
ip address 10.0.0.1 255.255.255.255
ip pim sparse-mode
Interface loopback 1
ip address 10.0.0.2 255.255.255.255
!
ip msdp peer 10.0.0.3 connect-source loopback 1
ip msdp originator-id loopback 1
Interface loopback 0
ip address 10.0.0.1 255.255.255.255
ip pim sparse-mode
Interface loopback 1
ip address 10.0.0.3 255.255.255.255
!
ip msdp peer 10.0.0.2 connect-source loopback 1
ip msdp originator-id loopback 1
B
RP2
A
RP1
C D
ip pim rp-address 10.0.0.1 ip pim rp-address 10.0.0.1
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Combining Anycast RP with Auto-RP
19
Interface loopback 0
ip address 10.0.0.1 255.255.255.255
Interface loopback 1
ip address 10.0.0.2 255.255.255.255
!
ip pim send-rp-announce loopback 0 scope 32
ip pim send-rp-discovery loopback 1 scope 32
!
ip msdp peer 10.0.0.3 connect-source loopback 1
ip msdp originator-id loopback 1
Interface loopback 0
ip address 10.0.0.1 255.255.255.255
Interface loopback 1
ip address 10.0.0.3 255.255.255.255
!
ip pim send-rp-announce loopback 0 scope 32
ip pim send-rp-discovery loopback 1 scope 32
!
ip msdp peer 10.0.0.2 connect-source loopback 1
ip msdp originator-id loopback 1
MSDP B
RP2
A
RP1
C
ip multicast-routing
ip pim autorp-listener
no ip pim dm-fallback
D
•Rapid RP failover of Anycast RP •No DM Fallback •Configuration flexibility of Auto-RP •Ability to disable undesired groups
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Anycast RP (PIM) - Operations
20
• FHR sends registers to RP1 • RP1 decapsulates packet, replicates it down RPT, joins SPT • Copy of register sent to RP2, source is RP1’s address • RP1 sends register-stop to FHR • RP2 decapsulates packet, replicates it down RPT, joins SPT • RP2 sends register-stop to RP1 • If no RPTs exist, discard register, send register-stop to sender, LHR and/or RP1
RP1 10.1.1.1
RP2 10.1.1.1
LHR
RP2
10.1.1.1
FHR FHR 10.1.1.1
PIM register
PIM register stop
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Anycast RP – PIM Config (NXOS)
21
B
RP2
A
RP1
feature pim
interface loopback1
ip address 10.10.10.10/32
ip router ospf 10 area 0.0.0.0
ip pim sparse-mode
interface loopback2
ip address 100.100.100.100/32
ip router ospf 10 area 0.0.0.0
ip pim sparse-mode
ip pim anycast-rp 100.100.100.100 10.10.10.10
ip pim anycast-rp 100.100.100.100 20.20.20.20
ip pim rp-address 100.100.100.100 group-list 224.0.0.0/4
feature pim
interface loopback1
ip address 20.20.20.20/32
ip router ospf 10 area 0.0.0.0
ip pim sparse-mode
interface loopback2
ip address 100.100.100.100/32
ip router ospf 10 area 0.0.0.0
ip pim sparse-mode
ip pim anycast-rp 100.100.100.100 10.10.10.10
ip pim anycast-rp 100.100.100.100 20.20.20.20
ip pim rp-address 100.100.100.100 group-list 224.0.0.0/4
C
feature pim
ip pim rp-address 100.100.100.100 group-list 224.0.0.0/4
feature pim
ip pim rp-address 100.100.100.100 group-list 224.0.0.0/4
D
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
ip multicast-routing
!
interface Loopback0
ip address 1.1.1.1 255.255.255.252
ip pim sparse-mode
ip ospf network point-to-point
!
interface Ethernet0/0
ip address 10.1.1.1 255.255.255.0
ip pim sparse-mode
!
interface Ethernet1/0
ip address 10.1.2.1 255.255.255.0
ip pim sparse-mode
!
router ospf 11
network 1.1.1.0 0.0.0.3 area 0
network 10.1.1.0 0.0.0.255 area 0
network 10.1.2.0 0.0.0.255 area 0
!
ip pim bidir-enable
ip pim rp-address 1.1.1.2 bidir
BiDir Phantom RP
22
RP: 1.1.1.2
ip multicast-routing
!
interface Loopback0
ip address 1.1.1.1 255.255.255.248
ip pim sparse-mode
ip ospf network point-to-point
!
interface Ethernet0/0
ip address 10.1.1.2 255.255.255.0
ip pim sparse-mode
!
interface Ethernet1/0
ip address 10.1.2.2 255.255.255.0
ip pim sparse-mode
!
router ospf 11
network 1.1.1.0 0.0.0.7 area 0
network 10.1.1.0 0.0.0.255 area 0
network 10.1.2.0 0.0.0.255 area 0
!
ip pim bidir-enable
ip pim rp-address 1.1.1.2 bidir
S P 30 Bit Mask 29 Bit Mask
OSPF requires P2P interfaces
Question: Does Bidir RP have to physically exist?
Answer: No. It can be a phantom address.
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Phantom RP with Auto-RP
23
ip pim send-rp-announce 1.1.1.2 scope 32 bidir ip pim send-rp-discovery Loopback1 scope 32 interface Loopback0
ip address 1.1.1.1 255.255.255.252
ip pim sparse-mode
ip pim send-rp-announce <[int] | [ip-address]> scope [group-list] [bidir]
Previously, Auto-RP could only advertise IP address on interface (e.g. loopback) as RP
New option has been added—now we can advertise any address on a directly connected subnet
In example below, Phantom RP address is being advertised through Auto-RP; the source of the Mapping packets are the address on Loopback
Available 12.4(7)T, 12.2(18)SXF4
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Intermittent Sources
24
“Intermittent” means applications / sources that temporarily stop
sending for > 3 minutes
(S,G) state times out. Initial packets lost during SPT switchover
Solutions:
PIM-Bidir or PIM-SSM (no data driven events)
Periodic keepalives or heartbeats
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Intermittent Sources – (S,G) Expiry Timer
25
(S,G) expiry timer:
Set on every router to maintain state for entire trading day (36000 seconds = 10 hours)
ip pim sparse sg-expiry-timer <secs>
Available 12.2(18)SXE5, 12.2(18)SXF4, 12.2(35)SE and NXOS
7010-1# sh run pim | in sg
ip pim sg-expiry-timer 36000 sg-list sg-expiry
7010-1# sh route-map sg-expiry
route-map sg-expiry, permit, sequence 10
Match clauses:
ip multicast: group 239.1.2.0/23
Set clauses:
Interconnecting PIM Domains
Interconnecting PIM Domains - NAT / Service Reflection
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Benefits of Multicast Destination NAT
28
• Address Collision
‒ Solves overlapping services in scoped address range
• Domain Separation
‒ Creates two PIM domains
‒ Edge router becomes source / receiver in each domain
• Redundancy
‒ Allows creation of A and B stream
• Source Network Issues
‒ Allows free selection and scoping of source subnet
• Translation or Splitting options:
‒ Multicast-to-Multicast
‒ Multicast-to-Unicast
‒ Unicast-to-Multicast
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multicast Service Reflection Interface
29
• Appears as multicast receiver in source domain
• Appears as multicast source in receiver domain
• Similar to loopback interface – logical interface always up
• Resides on unique subnet excluded from IGP updates
• Maintains information about:
Input interface
Private-to-public destination group mappings
Mask length which defines destination pool range
Source IP address of translated packet
PIM Domain A
PIM Domain B Vif 1 Interface
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Service Reflection Interface Configuration
30
Asssign Vif1 to globally unique IP subnet
Vif1 subnet to be used as source address of NATed packets
Advertise Vif1 subnet in routing protocol
Configure multicast routing for NATed address range not shown (PIM-SM, SSM, or Bidir-PIM)
interface Vif1
ip address 10.1.1.1 255.255.255.0
ip pim sparse-mode
!
router eigrp 1
network 10.0.0.0
no auto-summary
PIM Domain A
PIM Domain B
Vif1 Interface
224.1.1.0 to 239.1.1.0
224.1.1.1 to 239.1.1.1
. . .
224.1.1.255 to 239.1.1.255
Configure Vif1 & Routing:
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Service Reflection – Receiver / Group Range
31
interface Vif1
ip address 10.1.1.1 255.255.255.0
ip pim sparse-mode
ip igmp static-group class-map static
!
class-map type multicast-flows static
group 224.1.1.0 to 224.1.1.255
PIM Domain A
PIM Domain B
Vif1 Interface
224.1.1.0 to 239.1.1.0
224.1.1.1 to 239.1.1.1
. . .
224.1.1.255 to 239.1.1.255
Static IGMP groups pull streams from PIM Domain A to Border Router
Use IGMP Static Group Range to simplify configuration
Supported since 12.2(18)SXF5
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Service Reflection Parameters
32
interface Vif1
ip address 10.1.1.1 255.255.255.0
ip pim sparse-mode
ip service reflect Gig0/0 destination 239.1.1.0 to
239.1.1.255 mask-len 24 source 10.1.1.2
PIM Domain A
PIM Domain B
Vif1 Interface
224.1.1.0 to 239.1.1.0
224.1.1.1 to 239.1.1.1
. . .
224.1.1.255 to 239.1.1.255
Include input interface
Define destination pool range and mask length
Specify source IP address from Vif1 subnet
Gig0/0
Interconnecting PIM Domains - Static and Dynamic Models
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Interconnecting PIM Domains
• Static Forwarding
• Static Service Levels—Cable Model
• Dynamic Forwarding
• Hybrid Design
• Provider / Customer prefer least coordination
• Providers under contract to deliver stream
• Each side wants to limit organizational liability / coordination
• Provider / Customer have separate multicast domains
• Therefore:
– Traffic statically nailed up, no PIM Neighbors, no edge DR, no PIM Joins accepted, no RP shared, no MSDP peering
34
Brokerage
Content Provider
Financial Service Provider
Brokerage Brokerage
Content Provider
Content Provider
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Static Subscriptions with IGMP
Customers Want Ability to “Nail Up” Service
Existing Issues – ip igmp join-group <group>
Sends an IGMP report out the interface
Traffic gets punted to CPU
– ip igmp static-group <group>
Adds interface to OIL
Does not send IGMP report out the interface
Workarounds
– Separate router—Put IGMP join group on a dedicated router
35
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Virtual RP
36
Source Network
Customer
224.0.2.64
Destination Source
10.2.2.2
e0
e1
interface Ethernet0
ip address 10.1.2.1 255.255.255.0
ip pim sparse-mode
ip igmp static-group 224.0.2.64
Virtual RP
interface Ethernet1
ip address 10.1.2.2 255.255.255.0
ip pim sparse-mode
ip pim rp-address 10.1.1.1
ip route 10.1.1.1 255.255.255.255 10.1.2.5
router ospf 11
network 10.1.0.0 0.0.255.255 area 0
redistribute static subnets
ip pim rp-address 10.1.1.1
Feed is statically nailed up
Customer Edge router advertises
RP address from upstream interface
Every router in customer network needs
to know about the RP
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Edge Router is RP
37
Source Network
Customer
224.0.2.64
Destination Source
10.2.2.2
e0
e1
interface Ethernet0
ip address 10.1.2.1 255.255.255.0
ip pim sparse-mode
ip igmp static-group 224.0.2.64
RP
interface Ethernet1
ip address 10.1.2.2 255.255.255.0
ip pim sparse-mode
interface Loopback0
ip address 10.1.1.1 255.255.255.255
ip pim sparse-mode
ip pim rp-address 10.1.1.1
ip pim rp-address 10.1.1.1
Feed is statically nailed up
Customer Edge router is RP—so that
it will accept a non-connected source
Every router in customer network
needs to be know about the RP
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Edge Router is RP - Caveat
38
Source Network
Customer
224.0.2.64
Destination Source
10.2.2.2
e0
e1
interface Ethernet0
ip address 10.1.2.1 255.255.255.0
ip pim sparse-mode
ip igmp static-group 224.0.2.64
RP
interface Ethernet1
ip address 10.1.2.2 255.255.255.0
ip pim sparse-mode
interface Loopback0
ip address 10.1.1.1 255.255.255.255
ip pim sparse-mode
ip pim rp-address 10.1.1.1
ip pim rp-address 10.1.1.1
Feed is statically nailed up
Customer Edge router is RP—so that
it will accept a non-connected source
Every router in customer network
needs to be know about the RP
This Method Will Not Work with Future Versions of IOS
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Edge Router Proxy Registers to RP
39
Source Network
Customer
224.0.2.64
Destination Source
10.2.2.2
e0
e1
RP
interface Ethernet1
ip address 10.1.2.2 255.255.255.0
ip pim dense-mode proxy-register list 100
access-list 100 permit ip any any
ip pim rp-address 10.1.1.1
interface Loopback0
ip address 10.1.1.1 255.255.255.255
ip pim sparse-mode
ip pim rp-address 10.1.1.1
interface Ethernet0
ip address 10.1.2.1 255.255.255.0
ip pim sparse-mode
ip igmp static-group 224.0.2.64
Feed is statically nailed up
Customer Edge router has dense-mode on
IIF and proxy registers to RP
RP is configured inside customer network
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Edge Router is RP and MSDP Peer
40
Source Network
Customer
224.0.2.64
Destination Source
10.2.2.2
e0
e1
RP
interface Ethernet1
ip address 10.1.2.2 255.255.255.0
ip pim dense-mode
interface Loopback0
ip address 10.1.1.1 255.255.255.255
ip pim sparse mode
interface Loopback1
ip address 10.1.3.2 255.255.255.255
ip pim sparse mode
ip pim rp-address 10.1.1.1
ip msdp peer 10.1.3.1 connect-source Loopback1
ip msdp originator-id Loopback1
RP
interface Loopback0
ip address 10.1.1.1 255.255.255.255
ip pim sparse mode
interface Loopback1
ip address 10.1.3.1 255.255.255.255
ip pim sparse mode
ip pim rp-address 10.1.1.1
ip msdp peer 10.1.3.2 connect-source Loopback1
ip msdp originator-id Loopback1
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Edge Router is RP and MSDP Peer
41
Source Network
Customer
224.0.2.64
Destination Source
10.2.2.2
e0
e1
RP
interface Ethernet1
ip address 10.1.2.2 255.255.255.0
ip pim dense-mode
interface Loopback0
ip address 10.1.1.1 255.255.255.255
ip pim sparse mode
interface Loopback1
ip address 10.1.3.2 255.255.255.255
ip pim sparse mode
ip pim rp-address 10.1.1.1
ip msdp peer 10.1.3.1 connect-source Loopback1
ip msdp originator-id Loopback1
RP
interface Loopback0
ip address 10.1.1.1 255.255.255.255
ip pim sparse mode
interface Loopback1
ip address 10.1.3.1 255.255.255.255
ip pim sparse mode
ip pim rp-address 10.1.1.1
ip msdp peer 10.1.3.2 connect-source Loopback1
ip msdp originator-id Loopback1
Dense mode is required on the IIF so that the A flag will be set and MSDP will forward an SA
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Static Forwarding—Cable Model
42
Basic Service
‒ ip access-list standard basic-service
permit 239.192.1.0 0.0.0.255 ! Basic service channels
Premium Service
‒ ip access-list standard premium-service
permit 239.192.1.0 0.0.0.255 ! Basic service channels
permit 239.192.2.0 0.0.0.255 ! Premium service channels
Premium Plus Service
‒ ip access-list standard premium-plus-service
permit 239.192.1.0 0.0.0.255 ! Basic service channels
permit 239.192.2.0 0.0.0.255 ! Premium service channels
permit 239.192.3.0 0.0.0.255 ! Premium Plus service channels
Adapt Cable Model of Provisioning by qualifying multicast boundary with each of following:
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
interface Vlan6
ip igmp static-group 224.0.2.64
ip igmp static-group 224.0.2.65
ip igmp static-group 224.0.2.66
...
ip igmp static-group 224.0.2.80
Static Forwarding - Group Range Command
Subscribing dozens or hundreds of groups can be cumbersome with the static-group command:
The static group range command simplifies the config:
Available in 12.2(18)SXF5
43
class-map type multicast-flows
market-data group 224.0.2.64 to 224.0.2.80
interface Vlan6
ip igmp static-group class-map market-data
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Advantages of Static Forwarding
Provider and Customer Have Separate Multicast Domains
Each free to use any forwarding model, e.g. PIM-SM, PIM-SSM, PIM-Bidir
Each responsible for their portion of the delivery model—clear demarcation
Simple, straight-forward
Has traditionally been first choice for Financial Service Provider
44
Main Disadvantage
Customer unable to control subscriptions and bandwidth usage of last mile dynamically
As data rates climb this is more of a issue
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Dynamic Forwarding Options
Rising data rates and 24 hour trading drive the requirement for dynamic subscriptions
Methods:
– IGMP Membership Reports
– PIM Joins—*,G for PIM-SM and PIM-Bidir
– PIM Joins—S,G for PIM-SSM
45
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Source Network
Customer
224.0.31.20
Destination Source
10.2.2.2
e0
e1
IGMP
IGMP
PIM
Dynamic Forwarding – Provider Wants IGMP Report
Assumes that hosts sit on edge of customer network or breaks multicast delivery model
Stretches the original design and purpose of IGMP
In deployment today
– We can make this work dynamically today with a combination of:
ip igmp helper
ip igmp proxy-service
ip igmp mroute-proxy
Industry may want to recommend this model going forward
46
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Source Network
e0
IGMP
IGMP
interface Loopback1
ip address 10.3.3.3 255.255.255.0
ip pim sparse-mode
ip igmp helper-address 10.4.4.4
ip igmp proxy-service
ip igmp access-group filter-igmp-helper
ip igmp query-interval 9
interface Ethernet0
ip address 10.2.2.2 255.255.255.0
ip pim sparse-mode
ip igmp mroute-proxy Loopback1
ip pim rp-address 20.20.20.20
ip route 20.20.20.20 255.255.255.255 10.4.4.4
e1
Customer
e0 loopback1
PIM
10.4.4.0/24
47
Dynamic Forwarding – igmp mroute-proxy
igmp proxy service and helper are configured on loopback
Downstream interface is configured with igmp mroute-proxy
Every router in customer network needs to be know about the virtual RP
Virtual RP: 20.20.20.20
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Dynamic Forwarding – igmp mroute-proxy (Detail)
48
Source Network
e0
IGMP
(*, 239.254.1.0), 00:00:01/00:02:55, RP 20.20.20.20, flags: SC
Incoming interface: FastEthernet1/15, RPF nbr 10.2.2.2, RPF-MFD
Outgoing interface list:
Vlan194, Forward/Sparse, 00:00:01/00:02:55, H
e1
Customer
e0 loopback1
PIM
10.4.4.0/24
PIM (*,G) Join message is received on e0 interface and mroute state is created; igmp mroute-proxy command on interface causes special internal flag to be added to mroute
PIM (*,G) Join message filters up towards virtual RP
The first PIM (*,G) Join on e0 triggers an unsolicited IGMP report to be generated on the loopback1 interface
Host sends IGMP report and creates mroute state
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Dynamic Forwarding – igmp mroute-proxy (Detail)
49
Source Network
e0
IGMP
IGMP e1
Customer
e0 loopback1
PIM
10.4.4.0/24
When periodic IGMP query is run on loopback1 the igmp proxy-service command initiates a walk
through the mroute table looking for mroute-proxy flag;
IGMP report generated for each mroute with flag.
While mroute is kept alive (with PIM joins) IGMP
reports are forwarded
The igmp helper command directs the IGMP report
out the e1 interface
IGMP reports are dynamic - only
sent when there is interest in the customer
domain; however edge router does not respond to
queries from provider router
Consideration:
•More IGMP messages
•Complex configuration
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Source Network
Customer
224.0.2.64
Destination Source
10.2.2.2
e0
e1
RP
RP
RP
Dynamic Forwarding – PIM / MSDP
Provider accepts PIM join
– Sparse Mode
Provider must supply RP addr
Requires PIM Neighbor relationship
No RP on customer Side
One multicast domain
– Source Specific Multicast
Provider must supply S,G info
Requires PIM Neighbor relationship
MSDP
– Standard Interdomain Multicast
– Requires peering relationship
50
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Dynamic Forwarding – (S,G) PIM Joins
Works in situations ideal for SSM
No need to share RP info or use MSDP
Redundancy options:
– Host Side Host can join both primary and secondary servers—for both A and B streams
Host will need to arbitrate between primary and standby
– Network/Server Side Anycast Source—Hosts only join one server and network tracks server and forwards active
stream
51
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Market Data Design Whitepapers
52
Market Data Network Architecture (MDNA)
Trading Floor Architecture
Design Best Practices for Latency Optimization
IP Multicast Best Practices for Enterprise Customers
‒ http://www.cisco.com/go/financial
A Set of Four Documents that Cover All Aspects of Network and Application Design for Market Data Distribution
Label Switched Multicast
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
What is Label Switched Multicast ?
54
IP multicast packets are transported using MPLS encapsulation.
MPLS encoding for LSM documented in rfc5332.
Unicast and Multicast share the same label space.
MPLS protocols RSVP-TE and LDP are modified to support P2MP and
MP2MP LSPs.
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
LSM Protocols
55
For BUILDING LSP’s:
Multicast LDP (MLDP)
‒ Extensions to LDP
‒ Support both P2MP and MP2MP LSP
‒ RFC6388
RSVP-TE P2MP
‒ Extensions to unicast RSVP-TE
‒ RFC4875
For ASSIGNING FLOWS to LSPs:
• BGP
RFC6514
Also describes Auto-Discovery
• PIM
RFC6513
• MLDP In-band signaling
• Static
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
LSM Services
56
LSM architecture supports a range of services or “clients”
Clients use combination of multicast signalling and control plane
All LSM traffic is forwarded using MFI or LFIB mechanisms
Shares the same forwarding plane as unicast MPLS
LSM Forwarding (MFI/LFIB)
P2MP TE
VP
LS
Native
IPv4
mV
PN
IPv4
Native
IPv6
MLDP Control Plane
C-Multicast Signalling
Forwarding Plane
BGP / PIM / PORT / Static
Clients
m6
PE
m6
VP
E
IPv6
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
MLDP P2MP - Signalling
Egress router (leaf) receives PIM Join
Leaf sends mLDP label mapping to Ingress router (Root) (via core)
Ingress PE received one update due to receiver driven logic
57
Ingress
Router
(Root)
Leaf
Leaf
Leaf CE
Receiver
CE
Receiver
CE
Receiver
Source
Label Mapping
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
MLDP P2MP - State
Control Plane: 1 P2MP LSP
Forwarding Plane: 1 P2MP LSP replication
When leaf router wants to leave, message only sent to next branch point, not to ingress PE;
58
Ingress
Router
(Root)
Leaf
Leaf
Leaf CE
Receiver
CE
Receiver
CE
Receiver
Source
P
PE
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
MLDP MP2MP - Signalling
Leaf sends mLDP label mapping to Root, (just like P2MP)
On each link, label mapping sent in reverse direction (away from root), creating bidirectional MP2MP LSP
59
Ingress
Router
(Root)
Leaf
Leaf
Leaf CE
Sender/Re
ceiver
CE
CE
Sender/Re
ceiver
Label Mapping TO root
Sender/Rec
eiver
Sender/Rec
eiver
Label Mapping FROM root
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
MLDP MP2MP - State
Control Plane: 1 MP2MP LSP
Forwarding Plane: 4 P2MP LSP
Control plane state converted to set of P2MP replications in forwarding plane
60
Ingress
Router
(Root)
Leaf
Leaf
Leaf CE
Receiver
CE
Receiver
CE
Receiver
P PE Sender/Rec
eiver
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
RSVP-TE - Signalling
Leafs sends BGP Auto Discovery leaf to notify ingress PE
Ingress PE sends RSVP-TE Path messages to leaves
Leaves respond with RSVP-TE Resv messages
61
Ingress
Router
(Root)
Leaf
Leaf
Leaf CE
Receiver
CE
Receiver
CE
Receiver
Source
BGP Auto Discovery leaf updates or static configuration
Resv Path
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
RSVP-TE Example - State
Control Plane: 3 P2P sub-LSPs from the Root to the Leaves
Data Plane: The 3 P2P sub-LSP are merged into 1 P2MP for replication
When a leaf want to leave, the control message is sent all the way to ingress PE to remove the LSP
62
Ingress
Router
(Root)
Leaf
Leaf
Leaf CE
Receiver
CE
Receiver
CE
Receiver
Source
P
PE
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Applications of LSM
IPTV / Internet multicast transport
– draft-ietf-mpls-mldp-in-band-signaling-02
– 1-1 mapping between IP multicast flow and LSP
– Forwarding uses the global table (non-VPN)
VPLS
– draft-ietf-pwe3-p2mp-pw-00
– Use MLDP to create Pseudowires
Carriers Carrier service
– draft-wijnands-mpls-mldp-csc-01
– A provider offering services to another provider
63
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public 64
Applications of LSM (cont)
MVPN (Rosen Model)
– RFC6037
– Using MLDP MP2MP for the default MDT (MI-PMSI).
– Using MLDP or RSVP-TE P2MP for the data MDT (MS-PMSI).
– Same as GRE model, just the encapsulation changed.
MVPN (Dynamic partitioned MDT)
– draft-rosen-l3vpn-mvpn-mspmsi-05.
– Dynamic model of above.
– Using MLDP MP2MP for the dynamic MDT.
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
LSM Status
65
LSM Protocols Distinct Properties
MLDP
draft-ietf-mpls-ldp-p2mp-08
Dynamic Tree Building suitable for broad set Multicast Applications
FRR as optional capability
Receiver-driven dynamic tree building approach
P2MP RSVP-TE
RFC-4875
Deterministic bandwidth guarantees over entire tree (calculation overhead limits this to static tree scenarios)
Headend-defined trees
FRR inherent in tree setup
Useful for small but significant subset of Multicast Applications: Broadcast TV where bandwidth restrictions exist
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
LSM – Decision Points
MLDP and RSVP are both useful tree building protocols for transporting
multicast over MPLS.
It depends on the application and the scalability/feature requirements which
protocol is preferred.
Aggregation is useful to limit the number of LSPs that are created. Too much
aggregation causes flooding.
There are different options to assign multicast flows to LSP’s, PIM, BGP,
MLDP in-band signaling and static.
For general purpose MVPN we recommend MLDP for tree building and PIM
for assigning flows to the LSP.
66
High Availability
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Service Availability Overview
68
IP Host Components Redundancy
Single transmission from Logical IP address
‒ Anycast — Use closest instance
‒ Prioritycast — Use best / preferred instance
Benefit over anycast: no synchronization of sources needed, operationally easier to predict which source is used
‒ Signaling host to network for fast failover
RIPv2 as a simple signaling protocol
Normal configuration to inject source routes into IGP (OSPF/ISIS)
Dual Transmission with Path separation
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Source Redundancy: Approaches
69
Primary Backup Live-Live/Hot-Hot
Two sources: one is active and src’ing content, second is in standby mode (not src’ing content)
Heartbeat mechanism used to communicate with each other
Two sources, both are active and src’ing multicast into the network
No protocol between the two sources
Only one copy is on the network at any instant
Single multicast tree is built per the unicast routing table
Two copies of the multicast packets will be in the network at any instant
Two multicast trees on almost redundant infrastructure
Uses required bandwidth Uses 2X network bandwidth
Receiver’s functionality simpler:
Aware of only one src, failover logic handled between sources
Receiver is smarter:
Is aware/configured with two feeds (s1,g1), (s2,g2) / (*,g1), (*,g2)
Joins both and receives both feeds
This approach requires the network to have fast IGP and PIM convergence
This approach does not require fast IGP and PIM convergence
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Source Redundancy: Anycast/Prioritycast Signaling
Redundant sources (or NMS) announce Source Address via RIPv2
Per stream source announcement
Routers redistribute (with policy) into IGP
– Easily done from IP/TV middleware (UDP)
– No protocol machinery required—only periodic announce packets
– Small periodicity for fast failure detection
– All routers support RIPv2 (not deployed as IGP):
Allows secure constrained configuration on routers
70
Src
RIP (v2) Report (UDP)
Router
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Source Redundancy - Anycast/Prioritycast
Policies
– Anycast: Clients connect to the closest instance of redundant IP address
– Prioritycast: Clients connect to the highest-priority instance of the redundant IP address
Also used in other places
– e.g. PIM-SM and Bidir-PIM RP redundancy
Policy simply determined by routing announcement and routing config
– Anycast well understood
– Prioritycast: Engineer metrics of announcements or use different prefix length
71
Secondary 10.2.3.4/32
Rcvr 2 Rcvr 1
Primary
10.2.3.4/31
Example: Prioritycast with Prefixlength Announcement
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Anycast / Prioritycast Benefits
Sub-second failover possible
Represent program channel as single (S,G)
– SSM: single tree, no signaling; ASM: no RPT/SPT
Move instances “freely” around the network
– Most simply within IGP area
– Regional to national encoder failover options (BGP based)
No proprietary source sync protocol required
Per program failover
– Use different source address per program
72
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multicast Fast Convergence
IP multicast
– Failures/changes corrected by re-converging trees
– Re-convergence time is sum of:
Failure detection time + Unicast routing re-convergence time
~ #Multicast-trees x PIM re-convergence time
– “Typical” reconvergence times:
~ 200 msec initial tree rebuild (500 - 4000 trees convergence/sec for subsequent trees)
Same behavior with PIM and mLDP
Do not require RSVP-TE for general purpose multicast deployments
Sub 50 msec FRR possible for PIM or mLDP
– Make-before-break during convergence
– Use of link-protection tunnels
73
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multicast Only Fast ReRoute - MoFRR
Make-before-Break solution
Multicast routing doesn’t have to wait for unicast routing to converge
An alternative to source redundancy, but:
– Don’t have to provision sources
– Don’t have to sync data streams
– No duplicate data to multicast receivers
No repair tunnels
No new setup protocols
No forwarding/hardware changes
http://tools.ietf.org/html/draft-karan-mofrr-00
74
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
MoFRR - Concept Example
75
S
R
B Join Path
Data Path
Alt Path
Alt Data Path
Wasted Bandwidth
Wasted Bandwidth
R
Not
1. D has ECMP path {BA, CA} to S
2. D sends join on RPF path through C
3. D can send alternate-join on BA path
4. A has 2 oifs leading to a single receiver
5. When RPF path is up, duplicates come to D
6. But D RPF fails on packets from B
7. If upstream of D there are receivers, bandwidth is only wasted from that point to D
8. When C fails or DC link fails, D makes local decision to accept packets from B
9. Eventually unicast routing says B is new RPF path
rpf Path (RPF Join)
Alt Join (Sent on Non-rpf)
Data Path
Interface in oif-list
Link Down or RPF-Failed Packet Drop
D D
A A
B B C C
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Lin
e C
ard
Lin
e C
ard
Lin
e C
ard
Lin
e C
ard
AC
TIV
E
STA
ND
BY
Failure
AC
TIV
E
Periodic PIM Joins
GENID PIM Hello
Triggered PIM Joins
Multicast HA for SSM: Triggered PIM Join(s)
Active Route Processor receives periodic PIM Joins in
steady-state
Active Route Processor fails
Standby Route Processor takes over
PIM Hello with GENID is sent out
Triggers adjacent PIM neighbors to resend PIM Joins
refreshing state of distribution tree(s) preventing them
from timing out
76
How Triggered PIM Join(s) Work When Active Route Processor Fails:
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Automatic IP Multicast Tunneling
Automatic IP Multicast Tunneling:
–http://tools.ietf.org/id/draft-ietf-mboned-auto-multicast
Designed to provide a migration path to a fully multicast enabled backbone
Allows multicast to reach unicast-only receivers without the need for any explicit tunneling
Provide benefits of multicast wherever multicast is already deployed
–Hybrid solution
–Multicast networks get the benefit of multicast
Works seamlessly with existing applications
–Requires only client-side shim (somewhere in client) and router support (in some places)
Supports IPv4, IPv6, IPv4 mcast over IPv6, IPv6 mcast over IPv4
77
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Elements Required for Deploying AMT
AMT requires Multicast
AMT requires Source Specific Multicast
AMT Gateway
–Sits in the end device, home network
AMT Relay
– Site in the Service Provider network
AMT architecture
78
AMT Relay
AMT Gateway
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
AMT Components
• Gateway
• Initiates connection to multicast network via AMT Discovery message
• Discovery message sent to “well known” Anycast address
• May be a host (PC, Mac, Xbox, Android, ConnectedTV, iPad, …)
Running as a Java applet on host or embedded in an application
• Or part of home or enterprise gateway/router with LAN multicast enabled
• Relay
• Listens for AMT Discovery messages to build AMT tunnel to requesting gateways
• May be on a router at the unicast/multicast boundary or in an appliance near the boundary
• Part of the Service Provider infrastructure
79
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Elements Required for Deploying AMT
80
Mcast-Enabled ISP
Unicast-Only Network
Content Owner
Mcast-Enabled Local Provider
Multicast Traffic
Unicast Stream
Enables Multicast Content to a Large (Global) Audience
Creates an Expanding Radius of Incentive to Deploy Multicast
AMT Relay
AMT Gateway
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Elements Required for Deploying AMT
81
AMT deployment scenario Mcast-Enabled ISP Content Owner
Mcast-Enabled Local Provider
Enables Multicast Content to a Large (Global) Audience
Creates an Expanding Radius of Incentive to Deploy Multicast
AMT Relay
AMT Gateway
Mcast-Enabled Local Provider
Multicast Traffic
Unicast Stream
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Live-Live
Live-Live—Spatial Separation
– Two separate paths through network; can engineer manually (or with RSVP-TE P2MP )
– Use of two topologies (MTR)
– “Naturally” diverse/split networks work well (SP cores, likely access networks too), especially with ECMP
– Target to provide “zero loss” by merging copies based on sequence number
Live-Live—Temporal Separation
– In application device—delay one copy—need to know maximum network outage
82
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Cable Industry Example
Path separation does not necessarily mean separate parts of network!
– Carrying copies counterclockwise in rings allows single ring redundancy to provide live-live guarantee; less expensive network
Target in cable industry (previously used non-IP SONET rings!)
– IP live-live not necessarily end-to-end (STB), but towards Edge-QAM (RH*)— merging traffic for non-IP delivery over digital cable
– With path separation in IP network and per-packet merge in those devices solution can target zero packet loss instead of just sub 50msec
83
STBs
STBs
HFC1
HFC2 RH1b
RH1b
RH1a
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
cFRR - PIM/mLDP Break Before Make
84
RPF change on C from A to C:
1.Receive RPF change from IGP
2.Send prunes to A
3.Change RPF to B
4.Send joins to B
Same methodology, different terminology in mLDP
‒ RPF == ingres label binding
Some more details (not discussed)
A B
S(ource)
Cost: 10
C
Cost: 12
R(eceiver)
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
cFRR -PIM/mLDP Make Before Break
1. Receive RPF change from unicast
2. Send joins to A
3. Wait for right time to go to 4.
– Until upstream is forwarding traffic
4. Change RPF to A
5. Send prunes to B
Should only do Make-before-Break when old path (B) is known to still forward traffic after 1.
– Path via B failed but protected
– Path to A better, recovered
– Not: path via B fails, unprotected
Make before Break could cause more interruption than Break before Make !
85
A B
S(ource)
Cost: 10
C
Cost: 12
R(eceiver)
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multipath for IP Multicast
In unicast, multipath selection happens during packet forwarding
In multicast, multipath selection happens during RPF-selection for PIM join!
– Multipath selection happening whenever route from RPF-lookup has more than one path (like from IGP equal cost multipath)
– Also needs to be enabled
86
Source (S)
Receiver (D)
IP Packet
R1
R2 R3
?
PIM Join e.g. (S,G)
RPF Selection
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Cisco IOS IPv4 Per (S,G)
Improvements for ECMP
87
Added two per (S,G) ECMP alternatives to IPv4 IP multicast
‒ ip multicast multipath [ s-g-hash [ basic | next-hop-based]]
Basic: polarizing/predictable—but per (S,G):
‒ (S XOR G % Nlinks)
Next-hop-based: stable/non-polarizing
‒ Hash(S,G, Nbr-i) = bsr_hash(bsr_hash(S,G), Nbr-i ))
‒ Select Nbr-i | max({ Hash(S,G,Nbr-i) | NBr-i })
‒ Nbr-i is the IP address of the next-hop of a path; Bsr_hash is the hash function also used in the BSR protocol in PIM (creates random number out of its two parameters)
‒ Algorithm select the one neighbor for which the Hash(S,G,Nbr-i) is highest
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Next-Hop Load-Split Algorithm
Needed to have non-polarizing algorithm and non-assert-causing!
– Router-local hash to cause non-polarization would cause assert issue!
Also would like stability under re-convergence:
– Re-convergence causes interruption! More in multicast than unicast; when loosing/adding an ECMP path, traffic on unaffected paths should not need to re-converge!
– Polarizing algorithm is not-stable: change in number of ECMP path changes “modulo” of algorithm, reshuffling large percentage of flows unnecessarily!
Hash algorithm taken from BSR/RFC, better than XOR for this purpose
88
R4
R1 R2 R3
If Link to R1 fails, R4 Re-Converges Both Red Trees toward R2 and R3 without Affecting the Orange and Blue Trees that Already Used those Two Next Hops
Multicast in 802.11
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Background on Video and Wi-Fi Multicast
90
Streaming video requirements • Video codecs such as MPEG-2 are intolerant of packet loss
• Loss of one packet impacts multiple video frames
• Since many frames are “incremental”
• MPEG-2 requires a PLR of < 0.5%
Native Wi-Fi multicast is not a reliable service • Wi-Fi => Packet Error Rate 1 - 2%
• Corrected by ACKs for unicast
• For multicast there are no ACKs
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
MAC Layer Enhancement: MC2UC
91
Multicast source
Wired network
Multicast converted to unicast
WLC
Application:
‒ Broadcast video over Wi-Fi at Hotspots
Issue:
‒ Broadcast video is multicast on IP network
‒ But multicast over Wi-Fi is not reliable
‒ Leads to poor video quality
Multicast to Unicast Solution:
‒ Snoop IGMP request for video
‒ Convert video to unicast on Wi-Fi last hop
‒ Transparent to the client
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Video Stream Multicast Delivery Solution
92
1
2
5.5
6
9
11
12
18
24
36
48
54
M0
M1
...
M14
M15
802.11 Data Rates
B/G
N
Video Server
AP 1140
• IGMP state monitored for each client. Only send video to clients requesting
• Multicast packets replicated at AP and sent to individual clients at their data-rate
• Resource Reservation Control (RRC) used to prevent channel oversubscription. Works in conjunction with Voice CAC
• Stream Prioritization ensures important videos take precedence over others
• SAP/SNMP error message created when Channel Subscription violated
Technical Solution
Smooth, Reliable Video
• Video delivered reliably at 802.11n data rates
• Quality of Video protected in varying channel load conditions
• Prevents video flooding
• Prioritizes Business Video over other video
Video Impact
Default 802.11B/G mandatory data rates
Intelligence in the AP
QoS Marked on CAPWAP From WLC
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Video Stream Delivery Solution
93
Stream Prioritization • Identify specific Video Streams for preferential
QoS treatment
Resource Reservation Control
(RRC)
• Quality of Video Enforcement by denying client
when channel busy
• Video Bandwidth protection to prevent video from
consuming Wi-Fi channel
Multicast Direct
• Sends multicast video stream as unicast directly
to client
• Video QoS promotion
• Enables use of 11n data rates and standards
packet error correction
Monitoring • Client alert for insufficient bandwidth
• SNMP trap for QoS/bandwidth problem
Roaming Support (existing) • Roaming with pre-built multicast flows
• Proxy IGMP join (cross controller roam)
IGMP snooping (existing) • Prevents video flooding
Feature Overview
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public 94
Network Layer Enhancement
Improved multicast performance over wireless networks
Multicast packet replication occurs only at points in the network where it is required, saving wired network bandwidth
One Multicast Packet In CAPWAP Tunnels
One Multicast Packet In CAPWAP
Multicast Group
One CAPWAP Multicast Packet Out
Three CAPWAP Unicast Packets Out
Unicast Mechanism
Multicast Mechanism
Network Replicates Packet as Needed
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Multicast Mode Selection
95
Multicast mode and multicast group configured on WLC general interface
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Agenda
96
Multicast Market Overview
PIM Configuration notes
Interconnecting PIM domains
Label Switched Multicast
High Availability
Multicast in 802.11
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Questions?
97
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Call to Action…
Visit the World of Solutions:-
Cisco Campus
Walk-in Labs
Technical Solutions Clinics
Meet the Engineer
Lunch Time Table Topics, held in the main Catering Hall
Recommended Reading: For reading material and further resources for this session, please visit www.pearson-books.com/CLMilan2014
98
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Complete your online session evaluation
Complete four session evaluations and the overall conference evaluation to receive your Cisco Live T-shirt
Complete Your Online Session Evaluation
99
© 2014 Cisco and/or its affiliates. All rights reserved. BRKIPM-2008 Cisco Public
Final Thoughts
Get hands-on experience with the Walk-in Labs located in World of Solutions, booth 1042
Come see demos of many key solutions and products in the main Cisco booth 2924
Visit www.ciscoLive365.com after the event for updated PDFs, on-demand session videos, networking, and more!
Follow Cisco Live! using social media:
– Facebook: https://www.facebook.com/ciscoliveus
– Twitter: https://twitter.com/#!/CiscoLive
– LinkedIn Group: http://linkd.in/CiscoLI
100