Multi-Tech Systems MTASR1-100 - Manual (Page 12)

MTASR1-100 Owner’s Manual
12
1.3.2 Network Address
Every node on a network has an assigned address that other nodes use when communicating with it. For
Ethernet and token ring network network adapters, unique addresses are assigned at the factory. ARCNET
networks have user-definable addresses. For example, the address of an Ethernet and token ring network
adapter consists of a 6-byte address, half of which is a special number identifying the board's manufacturer.
The last half of the address is a unique number for the board assigned at the factory. This strategy virtually
guarantees that no two Ethernet or token ring network interface cards will ever have the same address and
prevents conflicts.
When separate networks are connected into an internetwork, a new addressing scheme is required. On
interconnected NewWare networks, each network segment has its own address, which is used for routing
purposes and differentiate each segment from the others.
In TCP/IP networks such as the Internet, every node has a numeric address that identifies both a network and
a local host or node on the network. This addess is written as four numbers separated by dots, for example
200.2.9.1. The assignment of addresses is arbitrary within a company or organization, but if the company
plans to connect with the Internet, it is important to obtain registered addresses from an outside agency to
conform with international addressing standards. Applications running in computers also have addresses that
other applications, either local or remote, use to communicate with the application. On TCP/IP networks, a
socket is a combination of an Internet address plus an application address.
Internet Protocol (IP)
Internet Protocol is a connectionless communication protocol that by itself provides a datagram service.
Datagrams are self-contained packets of information that are forwarded by routers based on their address and
the routing table information contained in the routers. Datagrams can be addressed to a single node or to
multiple nodes. There is no flow control, acknowledgment of receipt, error checking, and sequencing.
Datagrams may traverse different paths to the destination and thus arrive out of sequence. The receiving
station is responsible for resequencing and determining if packets are lost. IP handles congestion by simple
discarding packets. Resequencing and error handling are taken care of by upper layer protocols.
IP works on a number of local and wide area networks. When IP runs in the LAN environment on an Ethernet
network, for example, the data field in the Ethernet frame holds the IP packet and a specific field in the frame
indicates that IP information is enclosed. IP uses an addressing scheme that works independently of the
network addressing scheme. For example, every Ethernet adapter has a factory-assigned address for each
node.
IP Addressing
Every node on an IP network requires a 4-byte numeric address that identifies both a network and a local host
or node on the network. A typical IP network is shown if Figure 1-3. This address is written as four numbers
separated by dots, for example, 200.2.9.1. In most cases, the network administrator sets up these addresses
when installing a device.
LAN 1
Tech Systems ®
Ethernet Network Address 148.1.9.x
148.1.9.30
148.1.9.1 148.1.9.23
148.1.10.1
Server PC Workstation PC
148.1.9.20 148.1.9.22
WAN
Device
RouteFinder 100
Figure 1-3. Typical IP Network