Ring Sequence

Note: When cancelling a MIB override, the user may have to perform the switch and power-cycle procedure twice (as described in the steps below) to actually change the STH hub’s ring speed by the switch.

To return to switch control from an MIB overridden Ring Speed setting:

1.Regain switch control. Change the current switch setting and power- cycle the STH. Regardless of the ﬁnal desired speed, the user must toggle the switch opposite its current position and then power-cycle the STH to put a switch-position change into effect, cancelling the MIB override.

2.Select the desired ring speed. If the Ring Speed switch setting is not yet the desired setting (it may be the same as the former setting from the MIB command), the user must again change the switch setting and power-cycle the STH to complete the change from the MIB- commanded speed setting to the desired switch-set speed setting,

2.6.2Ring Sequence

When STH hubs are stacked, they are interconnected via the intelligent hub to create a larger ring network. The ring sequence for the stations on the ring (the order in which stations are logically arranged on the ring) is determined by the physical location of each TCU connection in the stack. It progresses in ascending stack number and port number order. The sequence is changed each time a station is inserted or de-inserted from a ring.

To determine the ring sequence, consider only those ports inserted into the ring. Begin with the STH numbered lowest in the stack and list (in ascending numerical order) the number of each inserted port. Repeatedly move to the next STH and list the inserted ports in numerical order until all ports inserted into the ring have been listed. The order is continuous, wrapping directly from the stack’s last inserted port to the ﬁrst—from the bottom of the list, right back to the top.

2.6.3Power Supply Requirements

Note: The STH has a universal power supply which will accept input power from 90 to 264 VAC, 47-63 Hz.

The power supply has two outputs of +5 volts and +12 volts. The maximum output power is 20 watts and the minimum efﬁciency is 65%

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42, 24, STHI-44, STH-22 specifications

Cabletron Systems was a pioneer in networking technology, and its STH series, particularly the STH-22 and STHI-44, 24, and 42 models, stand out in the history of networking equipment. These devices were designed for high-performance network management and offered a multitude of features that helped organizations manage their networking resources efficiently.

The STH-22 was a compact and efficient network switch, primarily developed to serve small to medium-sized businesses. One of its main features was its ability to support multiple user connections while offering low latency and high throughput. The STH-22 utilized advanced packet-switching technology to ensure data could move rapidly across the network, enhancing overall communication and productivity.

On the other hand, the STHI-44 model addressed the needs of larger enterprises. It featured advanced routing protocols and could handle a greater number of simultaneous connections, making it ideal for environments with high data traffic. The STHI-44 also incorporated redundancy features to minimize downtime, a vital requirement for businesses that relied heavily on continuous network availability.

The STH-24 and STH-42 models focused on versatility and scalability, catering to a broad range of networking needs. Both models provided extensive support for various networking protocols and featured robust hardware for enhanced durability. The STH-24 was designed for offices requiring mid-range capabilities, while the STH-42 targeted enterprises with more demanding networking requirements.

All STH series devices were built with ease of management in mind. They included user-friendly interfaces that allowed IT personnel to monitor traffic, configure network settings, and troubleshoot issues in real-time. Additionally, the devices supported SNMP (Simple Network Management Protocol) for seamless integration into existing network management systems.

Another defining characteristic of the Cabletron STH series was its commitment to security. These devices came equipped with features that permitted administrators to set access controls and monitor network activity, thereby safeguarding against unauthorized access and potential threats.

In summary, Cabletron Systems' STH-22, STHI-44, STH-24, and STH-42 models represent a significant advancement in networking technology. With their diverse features, high-performance capabilities, and user-centric design, they have served a critical role in optimizing network resources, ensuring businesses were equipped to handle increasing connectivity demands.