Zhang and Liu introduced Distributed-Line (DL) graphs in 2010 in order to consider topologies for P2P networks. A DL graph can locally change its topology, which makes it easy to update a distributed hash table when a user joins/leaves the network. Zhang and Liu discussed the properties of DL graphs in their paper, but their proofs lack the detailed discussions. In this talk, we reanalyze these properties and provide complete proofs. In particular, we focus on the distribution of in-degress and the diameter of DL graphs, together with a construction of DL graphs with small diameters.