{"id":13962,"date":"2026-08-31T21:20:03","date_gmt":"2026-08-31T19:20:03","guid":{"rendered":"https:\/\/3cxcloud.lt\/legacy-pbx-upgrade\/"},"modified":"2026-08-31T21:20:03","modified_gmt":"2026-08-31T19:20:03","slug":"legacy-pbx-upgrade","status":"publish","type":"page","link":"https:\/\/3cxcloud.lt\/en\/legacy-pbx-upgrade\/","title":{"rendered":"Legacy PBX upgrade"},"content":{"rendered":"
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LEGACY PBX UPGRADE<\/h1>\n

Siemens, UNIFY and Alcatel systems upgraded to 3CX \u2014 a 3CX Cloud LT solution<\/p>\n

Do you run a legacy Siemens, UNIFY (formerly Siemens) or Alcatel phone system? You do not have to replace it at once: we connect a modern 3CX to the existing system, both run together, and staff move across in stages \u2014 with no downtime.<\/p>\n

Request a survey<\/a>All solutions<\/a><\/div>\n<\/div>\n
<\/linearGradient><\/defs>Existing PBX<\/text>RUN TOGETHER<\/text>3CX<\/text>Modern 3CX<\/text>Siemens<\/text>UNIFY<\/text>Alcatel<\/text><\/svg><\/div>\n<\/div>\n<\/section>\n
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Siemens, UNIFY, Alcatel<\/span><\/p>\n

Which legacy phone systems do we upgrade?<\/h2>\n

Most often these are legacy Siemens and UNIFY (formerly Siemens) systems, as well as Alcatel. They still work, but expanding them, maintaining them and finding parts keeps getting harder.<\/p>\n<\/header>\n

LEGACY PBX<\/text>Siemens<\/text>UNIFY<\/text>Alcatel<\/text>3CX<\/text>modern system<\/text>What stays the same<\/text>Numbers<\/text>Extensions<\/text>Daily routine<\/text>Siemens, UNIFY and Alcatel<\/text><\/svg><\/div>\n