Juniper SRX650 SRX650-BASE-SRE6-645AP Fiche De Données

Codes de produits
SRX650-BASE-SRE6-645AP
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SRX Series for the branch checks the traffic to see if it is legitimate 
and permitted, and only forwards it on when it is. This reduces the 
load on the network, allocates bandwidth for all other mission-
critical applications, and secures the network from malicious users. 
The main purpose of a secure router is to provide firewall 
protection and apply policies. The firewall (zone) functionality 
inspects traffic flows and state to ensure that originating and 
returning information in a session is expected and permitted for 
a particular zone. The security policy determines if the session 
can originate in one zone and traverse to another zone. This 
architectural choice receives packets from a wide variety of clients 
and servers and keeps track of every session, of every application, 
and of every user. It allows the enterprise to make sure that only 
legitimate traffic is on its network and that traffic is flowing in the 
expected direction. 
To ease the configuration of a firewall, SRX Series for the branch 
uses two features—“zones” and “policies.” While these can be 
user-defined, the default shipping configuration contains, at a 
minimum, a “trust” and “untrust” zone. The trust zone is used 
for configuration and attaching the internal LAN to the branch 
SRX Series. The untrust zone is commonly used for the WAN or 
untrusted Internet interface. To simplify installation and make 
configuration easier, a default policy is in place that allows traffic 
originating from the trust zone to flow to the untrust zone. This 
policy blocks all traffic originating from the untrust zone to the 
trust zone. A traditional router forwards all traffic without regard 
to a firewall (session awareness) or policy (origination and 
destination of a session).  
By using the Web interface or CLI, enterprises can create a series 
of security policies that will control the traffic from within and in 
between zones by defining policies. At the broadest level, all types 
of traffic can be allowed from any source in security zones to any 
destination in all other zones without any scheduling restrictions. 
At the narrowest level, policies can be created that allow only one 
kind of traffic between a specified host in one zone and another 
specified host in another zone during a scheduled time period.
High Availability
Junos OS Services Redundancy Protocol (JSRP) is a core feature 
of the SRX Series for the branch. JSRP enables a pair of SRX 
Series systems to be easily integrated into a high availability 
network architecture, with redundant physical connections 
between the systems and the adjacent network switches. With 
link redundancy, Juniper Networks can address many common 
causes of system failures, such as a physical port going bad 
or a cable getting disconnected, to ensure that a connection 
is available without having to fail over the entire system. This 
is consistent with a typical active/standby nature of routing 
resiliency protocols. 
When SRX Series Services Gateways for the branch are 
configured as an active/active hA pair, traffic and configuration 
is mirrored automatically to provide active firewall and VPN 
session maintenance in case of a failure. The branch SRX Series 
synchronizes both configuration and runtime information. As a 
result, during failover, synchronization of the following information 
is shared:  connection/session state and flow information, IPSec 
security associations, Network Address Translation (NAT) traffic, 
address book information, configuration changes, and more. In 
Standby
SRX240
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High Availability
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SRX240
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Figure 2: High availability