Patent ID: 11968122
Assignee: SOOCHOW UNIVERSITY
Field: Digital communication (Electrical engineering)
Classification: CPC H  Y | IPC G  H

Claim 3:
4. The joint optimization method for delay and spectrum occupation in the cloud-edge collaborative network according to claim 1, wherein a formula of the target function is, G
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  ,, wherein |CR| represents a total quantity of the set of user requests, and CR is a second set of user requests; x(u,s)e,k is a binary variable, if a user request (u, s) is processed at a MEC server node e and the user request is transmitted through a kth path, wherein E represents a set of MEC servers, a value of the binary variable is 1, or otherwise the value is 0; R(u,s) represents a quantity of computing resources required for transmitting the user request (u, s); Me is a computing resource capability of the MEC server node e; W(u,s),(k,l)e,k presents a distance of a link (k, l) through which a kth working path of transmitting the user request (u, s) from a node s to the MEC server node e, Σe∈E,k∈Kx(u,s)e,k=1, ∀(u,s)∈CR, Σe∈E,k∈Kx(u,s)e,k=y(u,s), ∀(u, s)∈CR, and K represents a set of k paths; c represents a transmission rate of the user request in an optical fiber link, and is set to 3×105 km/s; and y(u,s) is a binary variable, if the user request (u, s) is migrated to a second layer, that is, a MEC server node e in a cloud area for processing, a value of the binary variable is 1, or otherwise the value is 0; τ is extra switch delay of transmitting the user request to the cloud area through a switch, α and β are parameters, w(u,s)(k,l)e,f is a binary variable, and if the user request (u, s) is transmitted to the MEC server node e and a spectrum slot with a sequence number off of the link (k, l) is occupied, a value of the binary variable is l, or otherwise the value is 0.