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First a few words about the names and acronyms used in this documentation.

As the name of this tool implies, the CVB GigE Vision™ Server is a server. The naming comes from networks where a server provides a service.
The service in this case is image transfer and device/camera control.
A client connects to a server to consume the service. So the client here would be the software receiving the image data and controlling the CVB GEV Server.

 

The CVB GEV Server needs a network interface (NIC) to work on.

A physical NIC is normally one network card.
One NIC is identified by its unique Media Access Control (MAC) address.
A NIC needs to have at least one Internet Protocol (IP) address to be assigned to it with which the CVB GEV Server can be associated with.
Every interface has a subnet mask assigned to it. This mask defines which IP addresses form one logical network.
By default only devices in the logical subnet can see each other.
Especially the automatic GigE Vision™ device discovery only works in one subnet.
To identify a service or an application based on an IP address a port number is used. Ports are managed by the CVB GEV Server library.

 

When using the CVB GEV Server library the local endpoint which is the local IP address/port combination refers to the IP address/port of the server.
The remote endpoint refers to a connected client.

 

GigE Vision™ is based on the User Datagram Protocol (UDP) which makes fast image data transfer possible.
UDP itself is a connectionless protocol, but the GEV protocol adds connection state via a heart beat (timeout of the connection after a certain time without communication), access control (Control Channel Privilege) and data reliability (Resend-mechanism) without impairing the high transfer rates.
For more information about the GigE Vision™ protocol and supported software and devices see https://www.machinevisiononline.org (Vision Standards/GigE Vision™).

 

GigE Vision™ itself describes only the way data is transferred and the transfer and connection related camera controls.
For the high level description of the camera’s features and general camera control the GenICam™ standard is referenced.
The aim of the GenICam™ standard is to provide a generic interface to multiple transport technologies.
Every GEV camera must describe its features via an XML description which is then used by the GenICam™ GenApi to provide a high level feature interface.
For more information about GenICam™ and its modules see https://www.genicam.org.

 

The CVB GEV Server takes care of both the GEV protocol handling and the GenICam™ GenApi description and feature handling.