Phone System

We maintain a proprietary and internal numbering plan for a private phone system. This numbering plan is invite only and is not publicly accessible.

12 Digit Variable Length Numbering Plan

The numbering plan is designed to match our internal needs and is based on the following format: | 12 Digit Variable Length Numbering Plan | | | |

Tier Code	Sub Code	Assignee Prefix	Subscriber Number
1 digits	2 digits	3 digits	Remaining Digits
N	XX	XXX	See Below

Where X is a digit from 0 to 9 and N is a digit from 2 to 9.

The first digit of the tier code must be a number from 2 to 9, as tier codes 0 and 1 are reserved for administration’s proprietary use.

Variable Subscriber Blocks

In the above numbering format, the remaining 6 digits for the subscriber number may not always be assigned in whole to one provider.

For example, providers may request 10, 100, 1000 or 10000 number blocks for allocation.

Providers are assigned a “Prefix”, a fixed sequence of digits infront of the digits that would make up their numbering block.

So for example:

Prefix
1-23-456-12345X	We own anything 0 - 9 on the digit X

Prefix Sizes Available

Prefix	Numbers Available
1-23-456-XXXXX	10 Numbers	0 - 9
1-23-456-XXXX	100 Numbers	00 - 99
1-23-456-XXX	1,000 Numbers	000 - 999
1-23-456-XX	10,000 Numbers	0000 - 9999

We do maintain larger blocks for allocation if the provider intends to sub-assign a significant portion of the space.

Prefix	Numbers Available
1-23-456-X	100,000 Numbers	00000 - 99999
1-23-456	1,000,000 Numbers	000000 - 999999

Tier Codes

Below is a list of the tier codes and their usecases:

Tier Code	Usecase	Link
0	Reserved for utility codes	↩
1	Reserved for administration’s proprietary use	↩
2	End User Assigments	↩
3	Org. Block Assignments	↩
4	Non-human Agent Assignments	↩
5	Unassigned	↩
6	Short Codes (6XXXX)	↩
7	Reserved for Future Use	↩
8	Reserved for Future Use	↩
9	Call Group Assignments	↩
*	Not yet implemented