Theory of Operation 27

The AirConnect Mobile IP (roaming across routers) feature enables a wireless client on the Internet to move from one subnet to another while keeping its IP address unchanged. The scanning and associating process continues for active wireless clients. This allows the wireless clients to find new APs and discard out-of-range or deactivated APs. By testing the airwaves, the wireless clients can choose the best network connection available.

Set the wireless client for Mobile IP as specified in the AirConnect Network

Interface User Guide.

Security

Security involves two distinct areas: authentication and privacy. Authentication ensures that only authorized users access the wireless network. Privacy ensures that communication between authenticated users and the network cannot be intercepted or overheard. The Access Control List provides authentication using the wireless LAN service area and a system administrator-supplied list of all the wireless client MAC addresses authorized to access the Home Service Area. Privacy is ensured by enabling the 40-bit WEP encryption option.

Supporting CAM and Continuously Aware Mode (CAM) stations leave their radios on continuously to PSP Stations hear every beacon and message transmitted. These systems operate without any

adjustments by the AP.

A beacon is a uniframe system packet broadcast by the AP to keep the network synchronized. A beacon includes the wireless LAN service area, the AP address, the Broadcast destination addresses, a time stamp, Delivery Traffic Indicator Maps, and the Traffic Indicator Message (TIM).

Power Save Polling (PSP) stations power off their radios for long periods. When a wireless client in PSP mode associates with an AP, it notifies the AP of its activity status. The AP responds by buffering packets received for the wireless client. The PSP-mode wireless client wakes up to listen to the AP beacon every nth Beacon Interval where n is a PSP-mode value from the 1 to 5-range; the Beacon Interval is set on the wireless client. When the wireless client wakes up and sees its bit set in the TIM, it issues a poll request to the AP for packets stored for it. The AP sends them to the wireless client and the wireless client goes back to sleep. A DTIM field, also called a countdown field, informs wireless clients of the next window for listening to broadcast and multicast messages. The AP sends the messages following the nth beacon where n is the DTIM interval defined in the AP. When the AP has buffered broadcast or multicast messages for associated wireless clients, it sends the next DTIM with a DTIM Interval value. This value decreases by '1' with each successive beacon. The AP sends broadcast and multicast messages immediately following the beacon where the DTIM value is '0.' To prevent a PSP-mode wireless client from sleeping through a DTIM notification, select a PSP mode value less than or equal to the DTIM value. PSP-mode wireless clients hear the beacons and awaken to receive the broadcast and multicast messages.

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3Com 09-1765-001 manual Security
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09-1765-001 specifications

The 3Com 09-1765-001 is a versatile and robust networking device designed to enhance various aspects of enterprise network environments. Known for its reliability and performance, this product stands out in the competitive field of networking hardware, making it a preferred choice for businesses aiming to optimize their network infrastructure.

One of the main features of the 3Com 09-1765-001 is its support for advanced network management protocols. This device is equipped with SNMP (Simple Network Management Protocol), which facilitates efficient monitoring and management of network devices. With SNMP, network administrators can keep track of bandwidth usage, device health, and performance metrics, enabling proactive maintenance and troubleshooting.

Additionally, the 3Com 09-1765-001 boasts impressive speed and connectivity options. It features multiple Ethernet ports that support various speeds, typically ranging from 10/100 Mbps, and is designed to provide fast data transfer rates necessary for modern applications. This ensures seamless communication between devices within the network, catering to the increasing demand for speed in data handling, especially in enterprises with heavy usage.

Security is another critical characteristic of the 3Com 09-1765-001. It incorporates essential security features designed to protect sensitive data and ensure safe network access. These features include support for VLANs (Virtual Local Area Networks), access control lists, and port security measures that help to segment network traffic and restrict unauthorized access.

The device is also designed with flexibility in mind, allowing for easy integration into existing network infrastructures. It can function as a standalone device or be easily integrated with other 3Com products, creating a comprehensive networking solution tailored to specific business needs.

In terms of physical characteristics, the 3Com 09-1765-001 is typically housed in a durable chassis designed to endure the rigors of a busy server room or data center. Its compact design also allows for easy rack mounting, optimizing space usage while ensuring efficient operation.

Overall, the 3Com 09-1765-001 represents a combination of advanced features, reliable technology, and user-friendly design, making it an excellent choice for organizations looking to enhance their network capabilities. With its emphasis on speed, security, and manageability, this device is well-suited for the complexities of modern enterprise networking.
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