DISTRIBUTION PATTERNS

Patterns that rule the way resources are distributed and access around the network at runtime

REMOTE FACADE

A Coarse-grained interface towards fine-grade objects that a client can use to request for services without knowing the services details

flowchart LR
subgraph mobile_device
end
subgraph remote_facade
end
subgraph map_web_services
end
mobile_device --addresses--> remote_facade
remote_facade <--complex interactions--> map_web_services
remote_facade --directions--> mobile_device

PROS

• decoupling between Client and Server
• no disconnection problems due to asynchronous request/response model
• server communication details are transparent to the mobile device

DATA TRANSFER OBJECT (DTO)

Pattern to communicate data in a serializable data chunk called container that are exchanged in communications between nodes

PROS

• reduction of the remote calls to services cause data are transferred in a single communication

REMOTE PROXY

Pattern that relies on all communication to travel to a proxy server that encode/decode communications to servers, applies filters evaluate request and perform heavy processing on the requests

PROS

• the proxy performs the heavy operation instead of the mobile node
• proxy works as an adapter for the services behind

OBSERVER

Pattern to implement one to many communications, a single object register for a specific subject and it’s notified when the state of the subject changes

flowchart TD
subgraph notification
D[subject]
E[observer 1]
F[observer 2]
D --notifies--> E & F
end
subgraph registration
A[subject]
B[observer 1]
C[observer 2]
C & B --register--> A
end

PROS

• decoupling between subject and observer
• one to many communication support by design

CONS

• not to much scalable since a single node as the responsibility for communication

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