Lesson plan

Point code

An SS7 point code is an address for the SS7 telephone switching system. It is similar to an IP address in an IP network. It is a unique address for a node (Signaling Point, or SP), used in MTP layer 3 to identify the destination of a message signal unit (MSU). Message contain an OPC (Originating Point Code) and a DPC (Destination Point Code); sometimes documents refer to it as a signaling point code. Depending on the network, a point code can be 24 bits (North America, China), 16 bits (Japan), or 14 bits (ITU standard, International SS7 network and most countries) in length. ANSI point codes use 24 bits, mostly in 8-8-8 format. ITU point codes use 14 bits in 3-8-3 format. Fourteen bit point codes can be written in multiple formats. The most common are decimal number, hexadecimal number, or 3-8-3 format (3 most significant bits, 8 middle bits, 3 least significant bits). Twenty-four bit point codes may be written in decimal, hexadecimal, or 8-8-8 format.

Back to article

Article summary

An SS7 point code is an address for the SS7 telephone switching system. It is similar to an IP address in an IP network. It is a unique address for a node (Signaling Point, or SP), used in MTP layer 3 to identify the destination of a message signal unit (MSU). Message contain an OPC (Originating Point Code) and a DPC (Destination Point Code); sometimes documents refer to it as a signaling point code. Depending on the network, a point code can be 24 bits (North America, China), 16 bits (Japan), or 14 bits (ITU standard, International SS7 network and most countries) in length. ANSI point codes use 24 bits, mostly in 8-8-8 format. ITU point codes use 14 bits in 3-8-3 format. Fourteen bit point codes can be written in multiple formats. The most common are decimal number, hexadecimal number, or 3-8-3 format (3 most significant bits, 8 middle bits, 3 least significant bits). Twenty-four bit point codes may be written in decimal, hexadecimal, or 8-8-8 format.

Key claims

No claims recorded.

Discussion questions

  1. Summarise the article in your own words. Which single claim would you verify first, and why?
  2. Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
  3. If two sources disagreed about one of these facts, what would you need in order to trust one over the other?

Bibliography

No sources recorded.

Key claims and bibliography are generated from the same tracked claims and sources as the article page.