In wireless network applications, packet length is a key factor in affecting packet loss probability, and channel scheduling protocol can effectively reduce packet length by permitting only a few nodes to update their data at each instant. This paper focuses on the sliding mode control (SMC) under the packet length-dependent lossy network. By analyzing the relation between the transmitted nodes number and the packet loss probability, the standard round-robin protocol (RRP) is extended to the multi-node case. Firstly, the multi-node RRP (MN-RRP) is designed under Bernoulli lossy network. After marking the first access node as the token, we construct the token-dependent SMC law to ensure the stability of the closed-loop system and the reachability of the specified sliding surface. Furthermore, we design the network mode-dependent round-robin-like protocol (NMD-RRLP) under Markov lossy network, in which more sensor nodes will be selected under the good network condition, vise versa. Finally, the proposed static output-feedback SMC approach is applied to the RLC circuit system.