SylkServer Lync Gateway


The goal of this project is to develop a software gateway that makes possible end-to-end interoperability between Microsoft Lync, a proprietary solution based on modified IETF SIP standards and foreign domains using XMPP foundation standards. The solution would then be used for federating real time communication services using multiple media like audio, chat, presence and screen-sharing between these Lync, SIP and XMPP protocols.

This would allow parts of an organisation to migrate away from using Lync proprietary solution while maintaining interoperability with other parts of the organisation that still make use of it.


The gateway will provide translations for the following signalling and media:

  • Signaling (Lync's version of SIP and XMPP)
  • Audio calls (RTP media)
  • Chat conversations (in-dialog SIP messages and XMPP stanzas)
  • Presence notifications (SIP/XMPP subscriptions)
  • Screen Sharing (using Remote Desktop Protocol)


The gateway will be inserted between two foreign domains, allowing each domain to use its own dedicated client to interoperate with the client in the remote domain. A Lync based domain will use a Lync client and an XMPP domain will use a modified XMPP client that is able to support audio calls using Jingle and screen sharing using RDP protocol. It is the responsibility of the customer to develop its client to support these standards.


The customer will provide a functional Microsoft Lync implementation both clients and servers and support for troubleshooting issues related to native Microsoft implementation.


The software will be provided as a .deb package. The software will install out of the box on the current Debian and Ubuntu system available at the moment of delivery. Source code will be provided using a version control repository.


The software license will be GPL and the copyright will remain with the author of the software. No intellectual property will be transferred.

Delivery Schedule

The delivery of the above mentioned features will take place over a twelve month period. After six month, a functional skeleton of the application will be available and at least one media type will be implemented, audio is the first candidate. Other media types will be subsequently added. After one year the software will have an official release. The support period starts.


Costs consists of one time development fees and subsequent recurrent support fees. The customer may decide to stop further funding if after the initial six month the results are not satisfactory. After release, 1st year support period is mandatory and may be cancelled after 12 months.

  • The development costs are 7000 Euro/month. The total costs of the project amounts to 84000 Euro.
  • Support fees covers software upgrades and troubleshooting for problems reported by customer. The support fees amount to 18% of project value for the first year and 12% for subsequent years.

Payment Schedule

  • Development Phase 1: 42,000 Euro for first six calendar months
  • Development Phase 2: 42,000 Euro for last calendar months
  • Support fee 1st year: 15,120 Euro
  • Support fee following years: 10,080 Euro

Payments are done quarterly in advance, billing cycle is every 3 months.