Ethernet and TCP/IP(Basic information)

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Ethernet =

Is a family of computer networking technologies for Local Area Networks (LAN).

TCP/IP=

TCP/IP is a set of communication protocols used for the Internet and other similar networks. It is named from two of the most important protocols in IT: the Transmission Control Protocol (TCP) and the

Internet Protocol (IP).

Ethernet and TCP/IP

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Ethernet-standards

Ethernet is the most known used network standard.

The first variants had a transmission rate of 10 Mbit/s (10BaseT)

The current variants work with 100 Mbit/s (100 BaseT) or 1000 Mbit/s (Gigabit Ethernet).

Each ethernet device has an own ethernet-address,

named MAC-ID (or Node number) for identifcation.

Structure: 6-Byte Hex e.g.: 00-C0-4D-01-28-5B

The first 3 Hex-values describes the manufacturer code,

the last 3 Hex-values are a continuously number.

PC

MAC-ID: 00-C0-4D-01-28-5B

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TCP/IP (Transmission Control Protocol/Internet Protocol)

- The standard port is a LAN-Port with RJ45 connection for CAT6 cable:

- Structure of a TCP/IP data package:

RJ45LAN-Port

- TCP/IP is the most used transmission protocol between network devices, like PCs and LAN-based periphery (Router, Printer) etc.

TCP/IP

CAT6 cable

User data

IP-address IP-addressSynchronisation e.g. IP

192.168.1.150 192.168.1.200

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TCP/IP (Transmission Control Protocol/Internet Protocol)

Logical addressing of the TCP/IP devices:

Each device in a ethernet with TCP/IP needs for the transmission a

1. Different logical IP-address,

2. Subnetmask

3. Standardgateway

Screenshot of Windows Networksettings

(only necessary for routing in other subnets)

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TCP/IP (Transmission Control Protocol/Internet Protocol)

1. IP-Address:

Structure: XXX.XXX.XXX.XXX (32Bit value with typ. Dot-Notation)

Valid address area 000.000.000.000 to 255.255.255.255

e.g.: 192.168.001.200

IP: 192.168.1.150

Example:

IP: 192.168.1.160

8-fold

LAN-switch

small PC-network

PC1

PC2 PC3

IP: 192.168.1.170

PC4

IP: 192.168.1.180

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2. Subnetmask :Normally the ethernet is designed for different networks which are connected together. So the network-classification was created.

For this the IP-addresses are subdivided in Net-ID and Host-ID. The Net-ID describes the possible numbers of subnets, and the Host-ID describes the possible no. of devices in the subnet.

A Subnet-Mask defines the Net-ID and Host-ID of the IP-address.

Structure of the Subnet-Mask:

255.0.0.0 (Class A)

255.255.0.0 (Class B)

255.255.255.0 (Class C)

TCP/IP (Transmission Control Protocol/Internet Protocol)

Definition of the possible nets and hosts: (Example)

Class B

Subnet: 255 . 255 . 0 . 0Possible IP-addresses: 192 . 168 . 001-255 . 001-255

Net ID Host ID

Class C

Subnet: 255 . 255 . 255 . 0Possible IP-addresses: 192 . 168 . 150 . 001 - 255

Possible IP-addresses

Net ID Host ID

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TCP/IP (Transmission Control Protocol/Internet Protocol)

Subnet A Subnet B

3. Standardgateway :The Standardgateway allows a routing between different subnets. For this a gateway (e.g.router) must be installed, with a gateway address. This address must filled in the Standardgateway of each device:

Gateway 1 Gateway 2Range: 192.168.1.2 - 255

192.168.1.1 192.172.3.1

Range: 192.172.3.2 - 255

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TCP/IP (Transmission Control Protocol/Internet Protocol)

DHCP (Dynamic Host Control Protocol):

Typical in company networks are dynamic addressing system via

a DHCP-server, which provide the IP-address after network-login:

Obtain IP-address automatically

Important note in use of the CG-S/IP-Interface:

A static IP-address is necessary!

It is possible to get a static IP-adress via

the dhcp-server. (IT-department)

Screenshot of Windows Networksettings

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Repeater

Switch

SwitchSwitch

RepeaterS

S

S

S

S

S

SS

S

R

R

R

R

S

S

S

S

S

S

S

Switch

Typical structure of a local company network based on the ethernet networking technology:

NAT = Network Access Translation

WIN-Server Firewall (NAT-Router)

W W W.Internet

LAN-Local Area NetworkIntranet with TCP/IP

Workplace 1

Workplace 2

Workplace x

LAN

Ethernet (LAN) – Local company computer network

Mail-Server

IP: 195.170.12.55Subnet: 255.255.0.0

IP: 195.170.15.70Subnet: 255.255.0.0

IP: 195.170.35.230Subnet: 255.255.0.0

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Ethernet – Decentral Intranet company network

r

Location U.K.

r

Location Germany

VPN

WWWInternet

VPN = Virtual Private Network Tunnel through the WWW

Typical structure of a intranet company network, with decentral locations: