The router queue of packets waiting to be sent also introduces a potential
cause of packet loss. Since the router has a finite amount of buffer memory to
hold the queue, a router which receives packets at too high a rate may
experience a full queue. In this case, the router ahs no other option than to
simply discard excess packets. If required, these may later be retransmitted by
a transport protocol.
Architecture of a router
Routers are often used to connect together networks which use different types
of links (for instance an HDLC link connecting a WAN to a local Ethernet LAN).
The optimum (and maximum) packet lengths (i.e. the maximum transmission unit (MTU))
is different for different types of network. A router may therefore uses IP to
provide segmentation of packets into a suitable size for transmission on a
network.
Associated protocols perform network error reporting (ICMP), communication
between routers (to determine appropriate routes to each destination) and remote
monitoring of the router operation (network management).
The operation of a simple modern router is described on a separate page. If
you want to know how the router actually works click HERE.
| 
