Keepalives are generally used between two devices to say "Hello, I'm still here." This is what routing protocol Hello messages do at a basic level, though they tend to contain more information than simple keepalives do.
Keepalives are used by many protocols; they're not confined to routing protocols. High availability protocols (HSRP, VRRP) use them, CDP, Spanning Tree, etc... It's a long list. A lot of data link protocols such as HDLC and Frame Relay also use them to ensure that links are functional. The rate that they are exchanged is protocol-dependant and usually configurable.
Protocols/links that require the use of keepalives generally exchange them by default -- simply enabling the protocol or link causes keepalives to be exchanged. The only time you should find yourself having to enable them explicitly is when they're not required for basic functionality, but can add some benefit. Frame Relay End-To-End keepalives and GRE Tunnel keepalives are the only examples that come to mind offhand.
Hi everyone, I would like to thank you in advance for any help you can provide a newcomer like myself!
Im studying the 100-105 book by Odom and am currently on the topic of Port security. I purchased a used 2960 and I'm trying to follow a...
While deploying a number of 18xx/2802/3802 model access points (APs), which run AP-COS as their operating platform. It can be observed on some occasions that while many of their access points were able to join the fabric WLC withou...
I am going to design and build an LAN network under a tunnel underground with long distance between the switches.
I will have 2 Catalyst switches and 8 Industrial IE3000, and they will be connected with fiber.
For now I am planning on use Layer-2 s...