Specifications

Niagara Release 2.3
Revised: May 22, 2002 Niagara Networking & Connectivity Guide
Chapter 1 Understanding Networking and IP Addressing
Networking using IP
1–16
• Routers can isolate problems—they keep problematic messaging from being
propagated to the other networks.
• Routers can connect networks that use different media access methods (i.e.,
protocols).
Disadvantages of routers:
• Routers can create potential bottlenecks in networks.
• Routers are generally more complex and expensive than bridges and repeaters.
• Certain protocols are not routable.
Brouters Brouters are hybrids of both a bridge and a router. The device functions like a router,
relaying data transmissions between networks, until it encounters a data packet that
uses a protocol with which it is unfamiliar. Then, it functions as a bridge would.
Advantages of brouters:
• Brouters combine the data-handling capabilities of a router with the protocol
transparency of a bridge.
Disadvantages of brouters:
• Brouters are generally more complex and expensive than other
internetworking devices.
Gateways Gateways perform protocol conversion between different types of networks or
applications. For instance, a gateway can be used to convert a TCP/IP data packet to
NetWare IPX. Gateways perform complete conversion from one protocol to another
rather than simply support one protocol from within another, such as IP tunneling. To
do this, gateways take data transmissions, strip off their original protocol stack, and
repackage them in the protocol stack of the destination network.
Advantages of gateways:
• Gateways can provide internetworking support for drastically different kinds
of networks.
Disadvantages of gateways:
• Gateways often produce compromises in speed, efficiency, and cost.
• Gateways are often specialized to a given task (i.e., file transfer).
• Gateways can be network bottlenecks due to the time it takes to translate
between protocols.
Networking using IP
In this next section, we focus on how things connect on a network using the Internet
Protocol (IP). These are the subtopics:
• What is IP?—gives an overview of the IP protocol.
• IP Addressing—talks about IP addresses, subnet masks, and IP address classes.