IP SLA

IP SLA is a tool provided by cisco IOS in the cisco devices which is used to monitor the network performance. Cisco IP SLA sends data packets to other cisco devices or IP device like a host and gets the reply from these devices. It collects the data received from the devices and analyzes them to measure the performance of the network.

Each IP SLA task is called an operation. Every operation has its own definition of the type of packet the router will generate, the destination and the source address.

The IP SLA can be configured to schedule the time at which it can send packets and the type of data to collect and the frequency at which it can send these packets.

Different types of IP SLA operations are mentioned below.

1)ICMP (echo, jitter)

2)RTP(VOIP)

3)TCP

4)UDP

5)DNS

6)DHCP

7)HTTP

8)FTP


Different IP SLA operations function in different way but they have the same concept.

IP SLA consists of two parts to be configured.
1)IP SLA router
2)IP SLA responder.

Configuring IP SLA

1)Creating IP SLA operation using "ip sla <number>" command
2)Define the operation type 
3)Frequency of the operation(optional)
4)Schedule the operation using the command "ip sla schedule <  > command.

Example:
--------

R1(config)#ip sla 1
R1(config-ip-sla)#icmp-echo 10.2.2.2
R1(config-ip-sla-echo)#frequency 15
R1(config)#ip sla schedule 1 start-time now life forever

The first line in the above configuration "R1(config)#ip sla 1" assigns a number to the operation.

The second line "R1(config-ip-sla)#icmp-echo 10.2.2.2" describes the type of operation as icmp-echo and the destionation host ip is 10.2.2.2. Which means R1 will send the icmp echos to 10.2.2.2.

The third line mentions about the frequency of the echos through the command "R1(config-ip-sla-echo)#frequency 15".

The last line "R1(config)#ip sla schedule 1 start-time now life forever" tells about the time to start the operation. In this command the operation is started now and it will run forever.