Available in single and dual versions, the IP400 Office PRI card provides single and dual primary rate trunk interfaces respectively. The PRI is available as either T1, E1 or E1R2MFC depending on the market.
T1 trunk cards incorporate an integral CSU/DSU, eliminating the need for an external unit. The CSU function allows the trunk to be put in loop-back mode for testing purposes. This can be set manually, using the monitor application, or automatically from a Central Office sending a Line Loop Back (LLB) pattern. The DSU function allows the T1 trunk to be shared between data and voice services.