C-6 User’s Reference Guide

If the WWW server on the Internet then tries to open a connection to the IP address of 200.1.1.40 with the appropriate Exported Service defined, the Netopia R9100 will look at the destination port and will find that it is destined for port 21 (FTP). The Netopia R9100 then looks at the internal user-defined exported services table and finds that any incoming IP traffic from the WAN port with a destination of port 21 (FTP) should be redirected to the IP address of 192.168.5.3 on the local LAN interface, which in this case is Workstation B.

Once the appropriate exported services are defined, there can be seamless communication between a host on the Internet and a host on the Netopia R9100’s local LAN interface.

Important notes

Even with the advantages of NAT, there are several things you should note carefully:

There is no formally agreed-upon method among router vendors for handling an all-zeros IPCP request. The majority of router vendors use the all-zeros IPCP request to determine when a dial-in host wants to be assigned an IP address. Some vendors however attempt to negotiate and establish routing with an all-zeros IP address. The Netopia R9100 will not allow routing to be established with an all-zeros IP address and the call will be dropped with an error logged in the Device Event History.

When using NAT it is most likely that the Netopia R9100 will be receiving an IP address from a “pool” of dynamic IP addresses at the ISP. This means that the Netopia R9100's IP presence on the Internet will change with each connection. This can potentially cause problems with devices on the Internet attempting to access services like WWW and FTP servers or AURP partners on the Netopia R9100’s local LAN interface. In this case, if a dynamic IP address is assigned to the WAN interface of the Netopia R9100 each time, the administrator of the Netopia R9100 will have to notify clients who want to access services on the Netopia R9100’s LAN interface of the new IP address after each connection.

With NAT enabled, there cannot be two or more of the same types of service accessible from the Internet on the LAN interface of the Netopia R9100. For example, there cannot be multiple FTP servers (Port 23) on the Netopia R9100's LAN interface that can be accessible by workstations on the Internet. This is because there is no way within the Netopia R9100 and IP to distinguish between multiple servers using the same port, in this case port 23.

Fictional IP addresses may be assigned on the Netopia R9100’s LAN interface. It is strongly recommended that for the Netopia R9100’s LAN interface, an IP address from the Class C address range of 192.168.X.X be used. This is because this range is defined by the IANA as an address space that will never be routed through the Internet and is to be used by private Intranets not attached to the Internet.

If the address range of 192.168.X.X is not used and another range of addresses such as 100.1.1.X is used instead, this address space can potentially overlap an address space that is owned by a user attached to the Internet. Thus if a user on the Netopia R9100’s LAN interface has an IP address of

100.1.1.2while the Netopia R9100’s LAN interface is 100.1.1.2 and the local host wants to access a host on the Internet with the address of 100.1.1.8, the Netopia R9100 has no way of knowing that the

200.1.1.8address is actually on the Internet and not on its local LAN interface, since the local LAN interface is assigned the IP address range of 200.1.1.1 to 200.1.1.14.

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Farallon Communications R9100 manual Important notes

R9100 specifications

Farallon Communications R9100 is a high-performance network device designed to meet the demanding needs of modern telecommunications. This robust system specializes in delivering reliable, efficient, and scalable solutions for various networking environments. Its architectural design integrates cutting-edge technologies that enhance performance while ensuring compatibility with existing infrastructure.

One of the standout features of the R9100 is its advanced routing capabilities. Equipped with powerful processors, it supports multiple routing protocols, including OSPF, BGP, and EIGRP. This flexibility allows network administrators to optimize data flow and maintain seamless connectivity across diverse network topologies. The R9100 also includes sophisticated Quality of Service (QoS) mechanisms, enabling prioritization of critical traffic, which is essential for latency-sensitive applications.

Another significant aspect of the R9100 is its support for various interfaces. Whether organizations require Ethernet, fiber, or wireless connections, the R9100 accommodates a broad range of interface options. This versatility ensures that it can be deployed in various environments, from large enterprise networks to smaller branch offices.

Security is a crucial consideration in today’s networking landscape, and the R9100 addresses this with built-in security features. These include stateful firewall capabilities, Intrusion Detection System (IDS), and comprehensive Virtual Private Network (VPN) support. Such features allow organizations to safeguard sensitive data and maintain compliance with industry regulations.

The R9100 also prioritizes ease of management. With a user-friendly interface and robust monitoring tools, network administrators can easily configure and manage the device. This capability facilitates rapid troubleshooting and performance tuning, ensuring minimal downtime and optimal user experience.

Energy efficiency is an additional characteristic that sets the R9100 apart from its competitors. Designed with eco-friendly technologies, it minimizes power consumption while maximizing output, making it an ideal choice for organizations looking to reduce their carbon footprint.

In conclusion, Farallon Communications R9100 stands out as a versatile and powerful network device that meets the complexities of modern telecommunications. With its advanced routing features, robust security measures, varied interface options, and energy-efficient design, the R9100 is a formidable player in the networking landscape. Organizations can rely on this solution to enhance their network performance and evolve alongside their growing technological needs.