E1 vs E1 PRI diff?

Hey guys,

What is the difference between and E1 and an E1 PRI?
The only thing I can find is that the E1 can use up to 32 channels with CAS or CCS and that the E1 PRI uses 30 B channels and 1 D channel with CCS?
Can someone help shed some light on this topic for me?

Thanks.

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Comments

pitviper

The difference is basically how the signaling and address information is relayed. CAS uses in-band signaling and CCS (ISDN PRI falls under this category) uses a dedicated channel (timeslot 16 I believe for E1). The result in a nutshell is that you get more available voice features because of the dedicated signaling channel, but you lose 1 voice channel.

tech-airman

sp@m wrote: »

Hey guys,

What is the difference between and E1 and an E1 PRI?
The only thing I can find is that the E1 can use up to 32 channels with CAS or CCS and that the E1 PRI uses 30 B channels and 1 D channel with CCS?
Can someone help shed some light on this topic for me?

Thanks.

sp@m,

E1 is a European implementation of the ITU DS1 standard. E1, like T-1, is an always on connection from the ISP to you, similar to DSL or Cable Internet access. Since the ISP dialed you, you have full use of all 31 channels for your bandwidth needs.

E1 PRI is the European implementation of the ISDN PRI standard. ISDN is more similar to dialup where you have to "dialup" to the ISP using the D channel. Another consequence of using a D channel is that for overall bandwidth not related to signalling, is at least 64 kbps LESS than pure E1 service. In other words, an E1 PRI bandwidth is the total of the ISDN B channels.

Did my post help?

Here's the "Dial-Up Technologies" webpage in the Internetworking Technology Handbook @ Cisco.com for more information:

Internetworking Technology Handbook - Dial-Up Technologies [Internetworking] - Cisco Systems