WebSphere MQ Everyplace supports a method of establishing logical
connections between queue managers, in order to send or receive data.
WebSphere MQ Everyplace clients and servers can communicate over two
types of connections, peer channels and client/server
channels.
Client/server channels have the following
attributes:
- They are dynamic, that is created on demand. This
differentiates them from WebSphere MQ connections which have to be explicitly
created.
- You can only establish the connection from the client-side.
- A client can connect to many servers, using a separate connection for each
server.
- The server-side queue manager can accept many connections
simultaneously, from a multitude of different clients, using channel managers
and channel listeners.
- They work through a firewall, if the server-side of the connection is
behind the firewall. (This depends on the configuration of the
firewall.)
- They are unidirectional and support the full range of functions
provided by WebSphere MQ Everyplace, including both synchronous and
asynchronous messaging.
- Note:
- Unidirectional means that the client can send data to, or request
data from the server, but the server-side cannot initiate requests of the
client.
Peer channels have the following attributes:
- They are dymanic (like client/server channels).
- You can establish the connection from either the client-side or the
server-side.
- A queue manager can connect to peer channel listeners on many other queue
managers, using a separate connection for each peer channel listener.
- Only one other external client or server can establish a peer channel to
the queue manager at any one time. This restriction means that
normally, you only use this type of connection between clients, as server
queue managers usually want to handle multiple incoming requests
concurrently.
- They are not generally used over a firewall, as it is difficult to
configure peer channels in this environment.
- They are bidirectional and support the full range of functions provided by
WebSphere MQ Everyplace, including both synchronous and asynchronous
messaging.
- Note:
- Bidirectional means that the queue managers on each end of the
connection can request and pass data over the connection.
Connections can have various attributes or characteristics, such as
authentication, cryptography, compression, or the transmission protocol to
use. Different connections can use different characteristics.
Each connection can have its own value set for each of the following
attributes:
- Authenticator
- This attribute causes authentication to be performed. This is a
security function that challenges the putting application environment or user
to prove their identity.
- Cryptor
- This attribute causes encryption and decryption to be performed on
messages passing through the connection. This is a security function
that encodes the messages during transit so that you cannot read them without
the decoding information.
- Compressor
- This attribute causes compression and decompression to be performed on
messages passing through the connection. This attempts to reduce the
size of messages while they are being transmitted and stored.
- Destination
- The server and port number for the connection.
Typically, authentication only occurs when setting up the
connection. All flows normally use compressors and cryptors.
For more detailed information about connections see Connections. Also, for more information about
authenticators, compressors, and cryptors, see Security.
Figure 2. WebSphere MQ Everyplace connection

You can establish WebSphere MQ Everyplace connections using a variety of protocols allowing them to connect in
a number of different ways, for example:
- Permanent connection, for example a LAN, or leased line
- Dial out connection, for example using a standard modem to connect to an
Internet service provider (ISP)
- Dial out and answer connection, using a CellPhone, or ScreenPhone for
example
WebSphere MQ Everyplace implements the communications protocols as a set of
adapters, with one adapter for each of the supported protocols. This
enables you to add new protocols.
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