Installation guide
BlackBerry Enterprise Solution Security
Protecting the BlackBerry Infrastructure connections 29
A BlackBerry device can bypass SRP connectivity and authentication by using the BlackBerry Router to connect
directly to the BlackBerry Enterprise Server. The BlackBerry Enterprise Server can communicate with the
BlackBerry Router using a combination of the SRP and BlackBerry Router authentication protocols.
SRP authentication
SRP is designed to perform the following actions when the BlackBerry Enterprise Server and BlackBerry
Infrastructure establish an authenticated connection and subsequently transfer data between them.
SRP action Description
authenticate the BlackBerry
Infrastructure to the
BlackBerry Enterprise Server
and the BlackBerry Enterprise
Server to the BlackBerry
Infrastructure
The BlackBerry Infrastructure and the BlackBerry Enterprise Server
authenticate with each other before they can transfer data. The
authentication handshake sequence depends on a shared secret encryption
key (the SRP authentication key) on both the BlackBerry Enterprise Server
and the BlackBerry Infrastructure. If at any point in the authentication
handshake sequence the authentication fails, SRP terminates the
connection.
exchange configuration
information between the
BlackBerry Enterprise Server
and the BlackBerry
Infrastructure
The BlackBerry Enterprise Server is designed to send a basic information
packet to the BlackBerry Infrastructure immediately following the initial
SRP authentication process. The packet format is designed to be
recognizable to both the BlackBerry Enterprise Server and the BlackBerry
Infrastructure, enabling both sides to configure the parameters of the SRP
implementation dynamically.
To support backward compatibility with older versions of the BlackBerry
Enterprise Server software, which terminate the SRP connection if they
receive unrecognized packets, the BlackBerry Infrastructure does not send
basic information packets to the BlackBerry Enterprise Server until the
BlackBerry Enterprise Server has sent a packet of the same format to the
BlackBerry Infrastructure.
send and receive transactions
between the BlackBerry
Enterprise Server and the
BlackBerry Infrastructure
If the connection between the BlackBerry Enterprise Server and the
BlackBerry Infrastructure terminates, the wireless network can queue up to
five undelivered messages for up to seven days. If there are more than five
pending messages, the BlackBerry Enterprise Server stores them in the
BlackBerry configuration database. The BlackBerry Infrastructure does not
store data to send to BlackBerry devices.
If the BlackBerry Infrastructure is not operational, the wireless network
discards the pending messages—the BlackBerry device does not receive the
message and the BlackBerry Enterprise Server does not receive an
acknowledgement packet from the recipient BlackBerry device. When the
BlackBerry Infrastructure is operational again, the BlackBerry Enterprise
Server resends messages for which it did not receive an acknowledgement
packet from a recipient.
SRP authentication process
Step Action Description
1 The BlackBerry Enterprise
Server sends its SRP ID, or UID,
to the BlackBerry
Infrastructure.
The BlackBerry Enterprise Server sends a packet to the BlackBerry
Infrastructure to claim its own UID.
2 The BlackBerry Infrastructure
sends a challenge string to the
BlackBerry Enterprise Server.
The BlackBerry Infrastructure sends a random challenge string to
the BlackBerry Enterprise Server.
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