Jerry, As discussed in today's NSI call a clearer naming scheme would be helpful for service definitions, the following is proposed (with thanks to Inder and Tomohiro): Service Capabilities Definition (SDC) - This is often referred to as the 'service definition', so from Jerry's document: 'The Service Definition (SD) is a machine readable textual document that identifies each attribute of the service and the range of values that attribute will allow'. ... and I think defines a default value? Service Request Description (SRC) - this is a request for a specific instance of a service. It is created by the Requester Agent when it assigns desired values to each of the attributes described in the SDC. The SRC is sent from the RA to the PA in a Connection Request. Service Instance Description (SID) - this is a description of an actual service instance, the attribute values reflect the values chosen and confirmed by the Provider Agent. Would these terms help clarify your service definition document? Guy _____________________________________________________________________ ** Guy Roberts, PhD Network Engineering & Planning * * Tel: +44 (0)1223 371300 * * City House Direct: +44 (0)1223 371316 * 126-130 Hills Road Fax: +44 (0)1223 371371 * Cambridge * CB2 1PQ E-mail: guy.roberts@dante.net<mailto:guy.roberts@dante.org.uk> D A N T E United Kingdom WWW: http://www.dante.net _____________________________________________________________________