Chapter 2
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2.5 Static Routing
The ADSL devices support IP Static Routing. With Static Routing, a Network
Administrator makes specific LAN IP addresses available for WAN access.
The easiest form of routing is establishing predefined routes through a network.
A router that has been programmed for static routing forwards packets out of
predetermined ports. Configuring static routing to a sub-network avoids the
overhead of dynamic routing.
The many benefits of Static Routing are that they form a more safe and secure
network system, since there is only one path a network is connected in to and
out of.
Another benefit is that it is more efficient in Resource Management. Since it
uses less bandwidth, the router CPU cycles trying to calculate routes are not
wasted and it also conserves memory.
2.6 Bridging
The ADSL devices support IEEE 802.1d Transparent Learning Bridge
connecting Ethernet LANs. Ethernet Bridging is a Data Link Layer function
connecting Ethernet addresses, independent of higher layer Internet protocols.
When IP routing is disabled and bridging is enabled in the unit, the incoming
frames are forwarded based on MAC layer addresses. The ADSL device
supports Transparent Bridging, which forwards frames one hop at a time
towards the destination. The Learning Bridge, which performs MAC address
learning, reduces traffic on the network by maintaining a table of MAC
addresses and interfaces associated with each address.
