SIP Peers Test

Session Initiation Protocol (SIP) is an ASCII-character-based signaling protocol designed for real-time transmission using Voice over IP (VoIP). In Speech Server, SIP establishes sessions with requests and responses. When Speech Server is connected to a client, session initiation and call control are handled over SIP.

The SIP protocol is hosted through a SIP peer, which connects Speech Server to the caller's endpoint. The SIP peer can be a VoIP client, SIP client, or traditional telephony client. In Microsoft Skype for Business server, SIP Peer communication includes internal SIP communications between servers (MTLS), between Server and Client (TLS) and between Front End Servers and Mediation Servers (MTLS). Administrators may want to monitor the SIP Peer communication on the target Microsoft Skype for Business server so that they can figure out where exactly there is a delay in sending/receiving the messages. The SIP Peers test exactly helps you analyze the same! This test provides the administrators with a detailed insight on the numerical statistics of the active connections, active TLS connections, outstanding messages, connections that are  flow controlled etc. In addition, this test helps you to figure out the time delay for each message in the outgoing queue and the rate at which outgoing messages were dropped.

Target of the test : A Microsoft Skype for Business server

Agent deploying the test : An internal/remote agent

Outputs of the test : One set of results for the target Microsoft Skype for Business server that is to be monitored.

Configurable parameters for the test
Parameters Description

Test Period

How often should the test be executed.

Host

The host for which the test is to be configured.

Port

The port at which the specified host listens. The default port is 5060.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Active connections

Indicates the number of established connections that are currently active.

Number

A connection is considered established when peer credentials are verified or the peer receives a 2xx response.

Active TLS connections

Indicates the number of established TLS (Transport Layer Security) connections that are currently active.

Number

A TLS connection is considered established when the peer certificate, and possibly the host name, are verified for a trust relationship.

Outstanding messages

Indicates the number of messages that are currently present in the outgoing queue.

Number

 

Average delay in outgoing queue

Indicates the average time for which the messages were delayed in the outgoing queue.

Secs

A high value for this measure is a cause of concern which may be due to the accumulation of messages in the outgoing queue. Generally, the server may drop client connections if it is in a throttled state and therefore, messages may be delayed in the outgoing queue for more than 32 seconds.

Flow-controlled connections

Indicates the number of conenctions that are currently flow-controlled.

Number

Whenever the number of transactions on a specific connection exceeds the above threshold, the connection is marked as flow controlled and the server doesn’t post any receives on it.

Flow-controlled connections dropped

Indicates the number of connections that are dropped due to excessive flow-control.

Number

A low value is desired for this measure.

Avg processing delay due to flow-control

Indicates the average time delay in message processing when the socket is flow-controlled.

Number

A low value is desired for this measure.

Incoming requests

Indicates the rate at which requests were received during the last measurement period.

Requests/Sec

This measure is a good indicator of the user load on the server.

Outgoings dropped rate

Indicates the rate at which outgoing messages timed out.

Timeouts/Sec

The outgoing messages may time out when they stay in the outgoing queue for a duration longer than required.

A low value is desired for this measure.