numbering plan

A numbering plan is a type of numbering scheme used in telecommunications. This is a set of rules used for making numbers. For example, most telephone numbers belong to the E.164 numbering plan, though that won't include internal extensions in some PABXs.The E.164 numbering plan for telephone numbers includes:Country calling codesRegional numbering plans, such as:the European Telephony Numbering Spacethe North American Numbering PlanVarious national numbering plans, such as:Telephone numbers in the United KingdomApart from the use of numbering plans for telephone numbers, they are also used in routing of SS7 signalling messages as part of the Global Title. In Public land mobile networks, the E.212 numbering plan is used for subscriber identities (e.g. stored in the GSM SIM) while E.214 is used for routing database queries across PSTN networks.
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