Two parts that very important on telecommunication network plan, is numbering and charging. Numbering system plan is to aim at identification uniquely every user (terminal) that connected to telecommunication network. This numbering system become a part that very important for routing plan on the network, also for administration process, among other things is to charging administration until to users level that severally, based on numbering system, to posses identification or unique address.
Numbering system generally already recommendation by CCITT to adopts by every country. With that recommendation than to make possible cooperation operational telecommunication inter country, so that between users in that countries to be able to build telecommunication connection each other, because on that recommendation also explained numbering system (address) until level terminal equipment (users).
CCITT Recommendation classified the numbering system in to four numbering scheme for different network type, that is:
- E163 Recommendation is a system or numbering plan for international telephone services.
- E164 Recommendation is system or numbering plan that developed from E163 recommendation, to fulfill requisites of ISDN era (Integrated Services Digital Network). On this recommendation applied system with longer total number and change several procedure.
- X121 Recommendation is system or numbering plan for international packet-switched network.
- F69 Recommendation is system or numbering plan for international telex service.
Principle from each that numbering scheme basically is same, and for adopts in one country, numbering system is possible to modification or matched with local condition.
