Overview

The gated Routing Daemon

NOTE

The gated Routing Daemon

gated (pronounced “gate D”) is a routing daemon that updates routing tables in internetwork routers. Developed at Cornell University, gated handles the Routing Information Protocol (RIP), External Gateway Protocol (EGP), Border Gateway Protocol (BGP), Open Shortest Path First (OSPF) routing protocol, and the Router Discovery Protocol (RDP), or any combination of these protocols.

Routing protocols are designed to find a path between network nodes. If multiple paths exist for a given protocol, the shorter paths are usually chosen. Each protocol has a cost or a metric that it applies to each path. In most cases, the lower the cost or metric for a given path, the more likely a protocol will choose it.

You cannot use System Administration Manager (SAM) to configure gated.

Upon startup, gated reads the kernel routing table on the local machine. gated maintains a complete routing table in the user space, and keeps the kernel routing table (in the kernel space) synchronized with this table.

In large local networks, multiple paths often exist to other parts of the local network. You can use gated to maintain nearly optimal routing to other parts of the local network, and to recover from link failures.

Advantages

gated offers the following advantages:

Dynamic routing eliminates the need to reset routes manually. When network failures occur, routes are automatically rerouted.

Dynamic routing facilitates adding and administering nodes.

Dynamic routing lowers the cost of operating complex Internet systems.

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Chapter 1