Digital Access Signalling System 1

Proprietary protocol providing ISDN services

Digital Access Signalling System 1 (DASS1) is a proprietary protocol defined by British Telecom to provide ISDN services in the United Kingdom.^[1] It is now obsolete, having been replaced by DASS2. This too will become obsolete over the coming years as Q.931, a European standard, becomes widely adopted in the EU.

References

^ "Introduction To Line Telecommunications". TLC. Retrieved 3 February 2024.

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