Update README.md

Author: eckelcu

README.md

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-# unimgr-xr
-OpenDaylight Unimgr for MEF Carrier Ethernet Services with Cisco IOS XR
+# OpenDaylight Unimgr for MEF Carrier Ethernet Services with Cisco IOS XR
+
+EVC Services based on LSO Architecture
+
+The team at Xoriant have been working on implementing Ethernet Virtual Connection (EVC) based Ethernet Services based on Lifecycle Service Orchestration (LSO) architecture proposed defined by MEF Forum (MEF). The implementation of these services has been done as part of OpenDaylight UniMgr open source project. These EVC services are expected to be offered by Service Providers to their clients. There are six such services standardized by MEF, namely Ethernet Private Line (EPL), Ethernet Virtual Private Line (EVPL), Ethernet Private LAN (EP-LAN), Ethernet Virtual Private LAN (EVP-LAN), Ethernet Private Tree (EP-Tree), Ethernet Virtual Private Tree (EVP-Tree).
+Here is a brief explanation of these services. Please also refer to MEF 6.2MEF 6.3, MEF 55MEF 55.1, MEF 10.3MEF 10.4 documents for the terminology used in this document and for a formal definition of each service.