The 9x group has been around since 1995. Since their arrival into the hacking and phreaking scene, scores of articles, programs, and wardialling scans have been made available. They are definitely worth checking out.
UK Switching Systems & line tests
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Intermediate UK Phreakers guide
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Time O Matic's system 8000
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Telecom. system and structures
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BT network admin spt systems development
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Switched route of tf setup networks
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South Western Bell codes
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Local vs. Net hacking
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Skytel Command Refernce Chart
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hacking skytel pager VMBs
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More info on SecurID
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Inpho on SecurID
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Cellular System ID List
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Info on Signalling
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SecurID All Over
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Exploring UK Prefix assignment
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Satellite communications
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Followup to hacking PMs
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Hacking Rolm PhoneMail
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Some information on ROLM PhoneMail systems
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TTYs/TTDs and Relay service
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dialups to most telco PSNs
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Playstation game development
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why pcs phones cant be cloned
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The PBX: History and hacking
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