Question

I need a good versus chart and explanation for choosing SSH over Telnet and SNMP. Provide a chart for comparison of SSH, Telnet and SNMP. and provide explanation on why recommend SSH over telnet and SNMP. I don't need the definition of Telnet, SSH and SNMP. Please focus on the recommendation part and comparison part. Thanks

Answer 1

SSH vs TELNET

Secure Shell, commonly known as SSH, and Telnet are two network protocols that have been used widely at one point in time or another. They are both used to connect to remote servers in order to facilitate some sort of communications. The primary difference, which also led to one superseding the other, is in security. SSH offers security mechanisms that protect the users against anyone with malicious intent while Telnet has no security measures whatsoever.

Telnet was designed to work within a private network and not across a public network where threats can appear. Because of this, all the data is transmitted in plain text, including passwords. This is a major security issue and the developers of SSH used encryptions to make it harder for other people to sniff the password and other relevant information. Telnet also omits another safety measure called authentication. This ensures that the source of the data is still the same device and not another computer. Without authentication, another person can intercept the communication and do what he wishes. This is also addressed in SSH as it uses a public key to authenticate the source of the data.

Why SSH?

1. SSH and Telnet commonly serves the same purpose
2. SSH is more secure compared to Telnet
3. SSH encrypts the data while Telnet sends data in plain text
4. SSH uses a public key for authentication while Telnet does not use any authentication
5. SSH adds a bit more overhead to the bandwidth compared to Telnet
6. Telnet has been all but replaced by SSH in almost all uses

SSH vs. SNMP

The majority of today's standard network monitoring tools are based on SNMP, which makes them “generalists” – able to offer a broad coverage of almost the entire network infrastructure, a big advantage. The downside, however, is the inability to penetrate beyond the surface of the devices being monitored, especially in terms of data collection and insight.

The reliance on limited protocols such as SNMP is the main restrictive factor of today's standard network monitoring tools. While many firewalls and routers support SNMP, they provide only a small subset of their running configurations through the protocol.

By contrast, more robust protocols such as SSH allow to access and extract an entire range of configuration data in network devices and in real time. SSH is also commonly used by engineers to troubleshoot devices. In this way, a tool that utilizes SSH may simulate human-like behavior, so that the data it's capable of reaching and analyzing in the network go far beyond what standard, SNMP based network monitoring tools can reach.

So essentially, using SSH for monitoring a network is like monitoring in reverse - Instead of looking for symptoms ie. which are the end result of a problem, they look for the possible causes ie. the beginning of a problem.