International Telecommunication Union

IP SYMPOSIUM FOR AFRICAKigali, Rwanda, 7-9 July 2003

A Policy Look at A Policy Look at IPv6IPv6

Greg JonesITU Telecommunication Standardization

Bureau greg.jones@itu.int

28 July 2003

Outlineo What is IPv6o Address space exhaustiono Relationship to topologyo Alternatives to IPv6o Network problemso Space allocation policyo Deployment difficultieso Roadblocks and solutionso ITU and IPv6o About the ITUBased on a paper by John Klensin, available

at:http://web/itudoc/itu-/com2/infodocs/015.html

38 July 2003

What is IPv6

o IPv6 (Internet Protocol, version 6) was developed by the Internet Engineering Task Force (IETF), starting in 1993,

o in response to a series of perceived problems,

o primarily exhaustion of the current, IP version 4 (IPv4), address space

48 July 2003

Address space exhaustion (1/3)

o Rate and scale of Internet growth was underestimated

o In 1970’s, 32-bit address space was thought to be adequate for long term

o Class system (A, B, C)o Internet routing is closely tied to the

separation of routing within a network and routing between networks

58 July 2003

Address space exhaustion (2/3)

o Routing within large networks became complex

o Sub netting introducedo Advent of PCs meant that each host could

no longer have a unique fixed IP address• dynamic address assignment

(reachability?)• private address spaces (leakage if

connected to public network)

68 July 2003

Address space exhaustion (3/3)

o In 1995, classless system was introducedo RIRs became more conservative with

respect to address allocationo Some believe IPv4 addresses will be

exhausted in 2-3 years, others in 10 years, others sooner, others much later.

o Rate of exhaustion influenced by technology (e.g. NATing) and RIR policies as well as growth

o Under-use of certain class A, B allocations

78 July 2003

Relationship to topology (1/3)

o An IP address is not similar to a telephone number

o An IP address is a routing addresso In telephony terms:

• a telephone number is more like a domain name

• an IP address is more like a SANC

88 July 2003

Relationship to topology (2/3)

o But analogies are imperfect• Telephone numbers identify a

circuit, a wire going somewhere, but are now portable

• IP addresses identify a terminal device, a computer, but can be:•dynamically assigned•translated (NATing)

98 July 2003

Relationship to topology (3/3)

Back to the basics of Internet:o Any host can access any other host

through uniform protocols and addresses

o Network is dumbo Intelligence at the edgeso Applications independent of networko Network does not change content

These differences are more important than the packet vs. switched models

108 July 2003

Alternatives to IPv6

o Application servers at boundary of public network, translate to private network, but these gateways can limit functionality

o NATing, VPNs, private spaces, but may force re-numbering NATing limits peer-to-peer

applications IPsec requires end-to-end

118 July 2003

Network Problems

o Routing table growth (IPv6 may help or hinder)

o Blocks allocated to ISPs to optimize routing limit portability across ISPs

o Security may or may not be improved

Expanding address space raises certain issues

128 July 2003

Space allocation policies

o RIRs allocate to LIRs (optimizes routing)

o If IPv6 policies are conservative, this may slow the adoption of IPv6

o If IPv6 policies are loose, this may lead to routing table problems and early exhaustion

138 July 2003

Deployment difficulties

o Dual stack: v4 and v6 in deviceso Tunnels: encapsulate v4 in v6 or v6 in

v4o Conversion gatewayso Convert networks

• from the edges• from the core• by islands, either geographic or by

application (3G)

148 July 2003

Potential roadblocks and solutions

o Cost of conversiono Lack of confidence in v6 softwareo Policies (will)

Consensus is that conversion is needed, but when and how will depend on many factors

158 July 2003

ITU and IPv6

o ITU’s mission includes providing information on new technologies to its membership, IPv6 is a good example

o A Tutorial Workshop was held in Geneva on 6 May 2002, see: itu.int/ITU-T/worksem/ipv6

o Further events are being considered

168 July 2003

What is ITU?

o International treaty organization founded in 1865 to facilitate international interconnection of telegraphy

o Unique partnership of industry and governmentso Three sectors:

• Development (aid to developing countries)• Radio (radio spectrum and satellite slot

allocations)• Standardization (formerly CCITT, for example

modem standards) (now called ITU-T; secretariat is called TSB)

o In ITU-T industry and government work together to develop mutually agreed non-binding Recommendations

178 July 2003

Goals of ITU-T

“The functions of the Telecommunication Standardization Sector shall be, bearing in mind the particular concerns of the developing countries, to fulfill the purposes of the Union relating to telecommunication standardization, as stated in Article 1 of this Constitution, by studying technical, operating and tariff Questions and adopting Recommendations on them with a view to standardizing telecommunications on a worldwide basis.”

188 July 2003

IP project–areas of study

o Integrated architectureo Impact to telecommunications access infrastructures of

access to IP applicationso Interworking between IP based network and switched-

circuit networks, including wireless based networkso Multimedia applications over IPo Numbering and addressingo Transport for IP-structured signalso Signalling support, IN and routing for services on IP-

based networkso Performanceo Integrated management of telecom and IP-based

networkso Security aspectso Network capabilities including requirements for

resource managemento Operations and Maintenance (OAM) for IP

198 July 2003

An example of ITU-T workENUM is an IETF protocol for mapping telephone numbers into the DNS. IETF asked ITU to facilitate government approval of ENUM implementations, given that telephony is still regulated in most countries

See: http://www.itu.int/ITU-T/inr/enum

o No real technical issueso Complex regulatory issueso After considerable discussion, most determined to be national matterso Under agreed procedures

o RIPE NCC will ask TSB if country approves ENUM delegation requesto If yes, it proceedso If no or no answer from country, it does not proceed (TSB objects)

o TSB does not itself evaluate requests in any way. RIPE NCC checks technical aspects of requests

208 July 2003

What ITU-T is not

o World-wide regulationo Consider issues that are national matterso Binding recommendationso Top-down decisionso Impose contractual terms or operating rules

on private companieso Work in non-transparent wayso Act bureaucraticallyo Have staff that decides policieso Collect fees other than membership fees

(with the exception of minor cost-recovery activities)

The ITU-T does not do the following:

218 July 2003

What is ITU’s Situation (1/5)

o ITU participation and coordination do not imply ITU control or government control.

o A good example is the international telephone numbering scheme, which is coordinated by ITU-T and is universally considered to work to the satisfaction of the general public; however, telephone services are not controlled by ITU-T and are provided by private companies

228 July 2003

What is ITU’s Situation (2/5)

o ITU-T is a dynamic, well-respected industry-government partnership (650 Sector Members)

o Examples of ITU-T Recommendations:• G.723.1 & G.729 - Speech coding for Voice

over IP and other applications • H.323 - Packet based multimedia

communication systems - the protocols behind Voice over IP, along with:

• H.245 - Control protocol for multimedia communications

• H.248 - Gateway control protocol (developed jointly with IETF)

• X.509 - Public-key encryption • V.90 - 56kbit/s PSTN modems - providing

ubiquitous worldwide internet access • G.99x series - xDSL Recommendations for

broadband access

238 July 2003

What is ITU’s Situation (3/5)

ITU-T Approval and publication times

before 1988 1989-1993 1993-1996 1997-2000 2001-2004

Approval time

4 years

2 years

18 months

9 months (exceptional

case: 5 months)

2-9

months

Publication time

2-4 years

2 years

1-1.5 year

6-12

months

3-9 months

Notes: 1. Pre-published Recommendations, available on ITU-T Website, from a few days

to four weeks after approval of the text. 2. Recs in force, pre-published, superseded/obsolete: available on ITU-T Website. 3. Forms of publication: paper, CD-ROM, electronic bookshop, online, etc.

4. FREE ONLINE ACCESS SINCE JANUARY 2001 (one free access per member, 3 free downloads for public) 5. “Approval time” counted between “determination/consent” and final approval

248 July 2003

What is ITU’s Situation (4/5)

o ITU-T working methods are fast and efficient: for example, 190 Recommendations have been approved under Alternative Approval Process in 2001, more than 60% in less than 2 months (ex. E.129, Representation of national numbering plans)

o ITU membership has increased in the private sector

o Non-government (non-profit) organizations can apply for ITU membership

258 July 2003

What is ITU’s Situation (5/5)

ITU-T–Electronic Publishing

o All Recommendations available onlineo Key databases (for example, telephone

country codes) available onlineo Working documents available online

See itu.int/ITU-T

268 July 2003

How does ITU-T Develop Recommendations?

o Consensus of Sector Members and Member States

o Work typically driven by Sector Memberso Open (for members), transparent,

bottoms-up processo Sensitive to national sovereignty: will only

cover matters not considered to be national

o Will not impose contractual terms or operating rules on private companies

Recommendations are not binding, but tend to be followed because they represent a true consensus.