Before revision: MMTel is one of the registered ICSI (IMS Communication Service Identifier) feature tags.uniform-resource-name-urn-list The MMTel standard is a joint project between the 3GPP and ETSI/TISPAN standardization bodies.
After revision: DescriptionMMTel is one of the registered ICSI (IMS Communication Service Identifier) feature tags.uniform-resource-name-urn-list The MMTel standard is a joint project between the 3GPP and ETSI/TISPAN standardization bodies.