Juniper JN0-636 Exam With Confidence Using Practice Dumps

• The SRX Series device is performing both source and destination NAT on this session because the traceoptions output shows that both source and destination IP addresses and ports are translated. The source IP address 192.168.5.2 is translated to 192.168.100.1 and the destination IP address 1.1.1.1 is translated to 192.168.5.1. The source port 0 is translated to 14777 and the destination port 80 is translated to 80. The traceoptions output also shows the rule and pool IDs for both source and destination NAT: 2/32770 and 1/1 respectively.
• This is the first packet in the session because the traceoptions output shows the flag flow_first_packet, which indicates that this is the first packet of a new session. The traceoptions output also shows the flag flow_first_src_xlate and flow_first_rule_dst_xlate, which indicate that this is the first time that source and destination NAT are applied to this session.

References:

• traceoptions (Security NAT) | Junos OS | Juniper Networks
• [SRX] How to interpret Flow TraceOptions output for NAT troubleshooting

• To solve the problem of using the same IPv4 address space as your company, you can identify two neutral IPv4 address spaces for address translation. This will allow you to use the same IPv4 address space as your company without any conflicts. Additionally, you can configure static NAT on the SRX Series devices to ensure that the traffic is properly routed between the two networks.
• Static NAT is a type of network address translation that maps a private IP address to a public IP address on a one-to-one basis. Static NAT is useful when you need to expose a server or device with a private IP address to the Internet or another network with a different IP address range. Static NAT also preserves the original source or destination IP address in the packet header, which can be useful for logging or auditing purposes1.
• Neutral IPv4 address spaces are IP address ranges that are not assigned to any specific organization or entity. They are usually reserved for special purposes, such as private networks, multicast, loopback, or documentation. Neutral IPv4 address spaces can be used for address translation when there is an overlap or conflict between two networks that need to communicate with each other. For example, you can use the 10.0.0.0/8, 172.16.0.0/12, or 192.168.0.0/16 address ranges, which are designated for private use, as neutral IPv4 address spaces for address translation2.

References:

• SRX Getting Started - Configure VPN tunnel for site-to-site connectivity
• SRX & J Series Site-to-Site VPN Configurator
• Resolution Guide – SRX - Troubleshoot Static NAT
• RFC 1918 - Address Allocation for Private Internets

In IPsec CoS-based VPNs, the number of IPsec Security Associations (SAs) associated with a peer is based on the number of forwarding classes configured for the VPN. The forwarding classes are used to classify and prioritize different types of traffic, such as voice and data traffic. Each forwarding class requires a separate IPsec SA to be established between the peers, in order to provide the appropriate level of security and quality of service for each type of traffic.