{"id":16993,"date":"2017-05-18T13:48:27","date_gmt":"2017-05-18T11:48:27","guid":{"rendered":"https:\/\/www.savecall.de\/colt-launches-voice-line-v\/"},"modified":"2026-08-06T14:46:50","modified_gmt":"2026-08-06T12:46:50","slug":"colt-launches-voice-line-v","status":"publish","type":"post","link":"https:\/\/www.savecall.de\/en\/colt-launches-voice-line-v\/","title":{"rendered":"Colt launches Voice Line (v)"},"content":{"rendered":"\n

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Colt launches Voice Line (v)<\/h1>\n<\/div>\n\n\n\n

Trusted Advisor for IT & Telecommunications Sourcing<\/h3>\n<\/div>\n\n\n\n
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Colt Voice Line v simplifies the switch to SIP Trunk<\/h2>\n<\/div>\n<\/div>\n\n\n\n
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Modern voice solution for companies<\/h2>\n\n\n\n
Is your telephony infrastructure ready for a smooth transition to modern SIP communication?<\/h6>\n\n\n\n
Colt Voice Line v is Colt’s flexible solution for businesses switching from traditional ISDN lines to IP-based voice services<\/a>. The service offers ISDN functionality via SIP trunking and enables a smooth migration within the Colt network.<\/p>\n\n\n\n
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To the point:<\/strong><\/p>\n\n\n\n
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High availability: at least 99.9 percent thanks to redundant fiber optic network<\/li>\n\n\n\n
Quality guarantee: SLAs ensure stable voice transmission and service<\/li>\n\n\n\n
Simple changeover: number portability and flexible upgrade or downgrade options<\/li>\n\n\n\n
Convenience functions: call forwarding, call hold, call blocking and call waiting included<\/li>\n\n\n\n
Transparent administration: online access to call detail records and invoices<\/li>\n<\/ul>\n\n\n\n
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The solution:<\/strong> Colt Voice Line (v) delivers ISDN functionality entirely via SIP trunking and enables a guided migration within the Colt network, without disrupting your existing number base.<\/p>\n\n\n\n
What this posting is about:<\/strong> How Colt Voice Line (v) simplifies the switch from ISDN to SIP trunk, which features and access options the service offers, and what this means for your telephony infrastructure.<\/p>\n\n\n\n
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Book a consultation<\/a><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n
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Table of Contents<\/h3>\n\n\n\n
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ISDN switch-off drives the shift to SIP trunks<\/a><\/li>\n\n\n\n
Colt Voice Line (v) Features<\/a><\/li>\n\n\n\n
How SAVECALL supports your switch to SIP Trunk<\/a><\/li>\n\n\n\n
Conclusion<\/a><\/li>\n\n\n\n
Frequently asked questions about Colt Voice Line (v)<\/a><\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n

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ISDN switch-off drives the shift to SIP trunks<\/h3>\n\n\n\n
The market for voice services has been changing since the ISDN switch-off announced in 2016 at the latest. Traditional PMX ISDN solutions within companies are gradually being converted to SIP trunks. Colt now wants to make this transition easier for companies with the new Colt Voice Line (v) product. Here, companies receive an ISDN service via SIP trunking, which simplifies migration. They then have a SIP-enabled connection delivered over the Colt IP network for the next step of the migration.<\/p>\n\n\n\n
Colt Voice Line (v) Features<\/h3>\n\n\n\n
The features include:<\/p>\n\n\n\n
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SLAs for the highest service quality<\/li>\n\n\n\n
Availability of at least 99.9%<\/li>\n\n\n\n
Transmission via Colt’s redundant and fail-safe fiber optic network<\/li>\n\n\n\n
Simple number portability when changing provider to Colt<\/li>\n\n\n\n
24-hour customer service<\/li>\n\n\n\n
Online access to call detail records, invoices and reports<\/li>\n\n\n\n
Call functions: call waiting, call forwarding, call distribution, call barring, call hold, etc.<\/li>\n<\/ul>\n\n\n\n
Access options include wDSL, ULL, 3rd party Ethernet. Furthermore, both upgrades and downgrades are possible at any time.<\/p>\n<\/div>\n<\/div>\n\n\n

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How SAVECALL supports your switch to SIP Trunk<\/h3>\n\n\n\n
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As a carrier-independent sourcing partner, SAVECALL compares Colt Voice Line (v) with more than 80 other carriers and SIP trunk providers to find the right solution for your numbers, sites and existing phone system. We also review Colt SIP Trunk integration with Microsoft Teams<\/a> for you. We support you from provider selection through contract negotiation to a smooth migration to SIP trunk.<\/p>\n\n\n\n
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Conclusion<\/strong><\/h3>\n\n\n\n<\/div>\n\n\n\n
With Voice Line (v)<\/strong>, Colt offers an attractive migration solution for medium-sized companies with transparent prices and a simpler platform for extensions and additional components. Are you interested in Colt Voice Line or would you like to find out more about SIP trunks and UCaaS<\/a>? Use our online check and see an overview of providers and prices for your location.<\/p>\n\n\n\n
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Book a consultation<\/a><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n
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$\"Frank$ <\/figure>\n<\/div>\n\n\n\n
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Written by<\/p>\n\n\n\n
Frank Frommknecht<\/h3>\n\n\n\n
Key Account Consultant, SAVECALL<\/strong><\/p>\n\n\n\n
Has supported companies for over 20 years in selecting and optimising their connectivity solutions. His focus: making complex telecommunications understandable from the customer\u2019s perspective and finding the right strategic solution.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n
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Why<\/h2>\n\n\n\n
$\"\"$ <\/figure>\n<\/div>\n<\/div>\n\n\n\n
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Telecom & IT sourcing. Worldwide. Carrier-independent.<\/h3>\n\n\n\n
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Selection & operation of worldwide connectivity & cloud infrastructure. Without vendor risk & unnecessary costs.<\/p>\n\n\n\n
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80+ carriers worldwide<\/li>\n\n\n\n
One point of contact<\/li>\n\n\n\n
One SLA<\/li>\n\n\n\n
One portal: mySAVECALL<\/li>\n\n\n\n
Min. 20% savings<\/li>\n<\/ul>\n<\/div>\n\n\n\n
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Book a consultation<\/a><\/div>\n<\/div>\n<\/div>\n\n\n\n
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25+
years of experience<\/h2>\n<\/div>\n\n\n\n
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Learn more<\/a><\/h5>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n
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40+
Employees<\/h2>\n<\/div>\n\n\n\n
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Learn more<\/a><\/h5>\n<\/div>\n<\/div>\n\n\n\n
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80+
Partner<\/h2>\n<\/div>\n\n\n\n
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Learn more<\/a><\/h5>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n
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1400+ Clients<\/h2>\n<\/div>\n\n\n\n
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Learn more<\/a><\/h5>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n
<\/p>\n\n\n
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Sources<\/h3>\n\n\n\n
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Colt Technology Services: ISDN Services \/ Colt Voice Line Datasheet<\/a><\/li>\n\n\n\n
Colt Technology Services: SIP Trunking Product Page<\/a><\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n\n
<\/p>\n\n\n
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Frequently Asked Questions<\/h2>\n<\/div>\n<\/div>\n\n\n
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Frequently asked questions about Colt Voice Line (v)<\/h3>\n\n\n\n
What is Colt Voice Line (v)?<\/strong>
Colt Voice Line (v) is a Colt product that delivers classic ISDN functionality over SIP trunking. Companies receive an ISDN service that already runs on a SIP trunk basis, together with a SIP-enabled connection over the Colt IP network. This makes the next migration step towards modern IP-based voice services easier, without forcing companies to replace their entire phone system infrastructure at once. Colt positions the product as a bridge between the ISDN switch-off and a full SIP trunk migration for mid-sized and larger companies.<\/p> <\/div>
How does the migration from ISDN to SIP trunk work with Colt Voice Line (v)?<\/strong>
With Colt Voice Line (v), companies first receive an ISDN service delivered via SIP trunking. A SIP-enabled connection over the Colt IP network then becomes available, preparing the switch to a full IP-based phone system. This allows the migration to be planned in stages instead of changing numbers, devices and phone system all at once. Access options such as wDSL, ULL or 3rd party Ethernet allow a connection tailored to the site throughout the transition.<\/p> <\/div>
What advantages does Colt Voice Line (v) offer over classic ISDN?<\/strong>
Colt Voice Line (v) offers availability of at least 99.9 percent over a redundant, fail-safe fiber optic network, plus SLAs for stable voice quality. It also includes simple number portability, flexible upgrade and downgrade options, and convenience functions such as call forwarding, hold, blocking and call waiting. An online portal gives companies transparent access to call detail records, invoices and reports, something classic ISDN typically cannot offer in this form.<\/p> <\/div>
What access options are available for Colt Voice Line (v)?<\/strong>
Access to Colt Voice Line (v) is possible via wDSL, ULL (unbundled local loop) or 3rd party Ethernet. This allows the service to be adapted to different site conditions, regardless of whether a suitable fiber or copper connection is already in place. According to Colt, upgrades and downgrades of the booked capacity are possible at any time, so companies can flexibly adjust their connection to growing or shrinking requirements without changing provider.<\/p> <\/div>
Is number portability possible with Colt Voice Line (v)?<\/strong>
Yes. Colt Voice Line (v) supports porting existing numbers when switching to Colt, so companies can keep their established phone numbers. This significantly reduces the organisational effort of migration, since customers, partners and internal processes do not need to be switched to new numbers. Combined with flexible access options and guaranteed availability of 99.9 percent, the switch can be carried out with minimal disruption to daily business.<\/p> <\/div>
Why should companies switch to SIP trunk now?<\/strong>
The market for voice services has been changing since the ISDN switch-off was announced in 2016: traditional PMX ISDN solutions are gradually being replaced by SIP trunks. Companies that migrate early avoid short-term pressure and can plan the switch in a structured way, for example with a product like Colt Voice Line (v), which already delivers ISDN functionality via SIP trunking. SAVECALL compares providers on a carrier-independent basis to find the solution that fits your existing phone system.<\/p> <\/div> <\/div>\n\n\n
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