public void AddOrUpdateTest()
        {
            var connectionCollection = new ConnectionCollection <Guid>(
                new TimeSpan(0, 10, 0));
            var conn1 = Guid.NewGuid();
            var int1  = Guid.NewGuid();
            var conn2 = Guid.NewGuid();
            var int2  = Guid.NewGuid();

            connectionCollection.Add(
                int1,
                conn1,
                Guid.NewGuid());
            connectionCollection.Add(
                int2,
                conn2,
                Guid.NewGuid());

            ConnectionCollection <Guid> .ConnectionNode node;
            Assert.IsTrue(connectionCollection.GetConnection(
                              int1, out node));
            Assert.AreEqual(conn1, node.ExternalConnection);
        }