To　analyze　the　long-run　sample　average　performance　metrics　such　as　throughput,　latency　and　average　buffer　occupancy　etc.,　the　component　library　of　Parallel　Object-Oriented　Specification　Language　(POOSL)　was　extended　with　the　technique　of　regenerative　cycles.　Based　on　the　extended　POOSL,　the　performance　analysis　model　for　the　Selective　Repeat　Sliding　Window　Protocol　was　built.　Results　of　the　quantitative　performance　analysis　on　the　influence　of　the　parameters　such　as　the　window　size,　the　packet　size　and　the　timeout　period　were　given.　The　experimental　results　show　that　the　extended　POOSL　is　effective　for　the　quantitative　analysis　on　the　long-run　sample　average　performance　metrics.