Black Box Modular Switches, LE14XXA manual Frame Buffering and Latency

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ack Box Modular SwitchesInstallation and User Guide (8/99)

The RJ-45 ports run at 10/100Mbps with N-wayauto-negotiation capability, whereas e fiber port runs at 100Mbps with half- or full-duplex capability manually selected. The fault condition is full-duplex. Internal jumpers settings allow technicians to set the 100Mb ber port to half-duplex mode. (See Section 3.4).

n LE14XXA Combo 4-port modules, there are three LED’s for each RJ-45 port, which indicate atus as described for the LE1426C in Section 2.2.4 above. The fiber port will run at 100Mbs eed at all times, and has LEDs that indicate status the same way as described for the Fiber 4- rt modules in Section 2.2.2 above.

2.6Frame Buffering and Latency

The Black Box LE14XXA-Series are store-and-forward switches. Each frame (or cket) is loaded into the Switch’s memory and inspected before forwarding can occur. This chnique ensures that all forwarded frames are of a valid length and have the correct CRC, i.e., e good packets. This eliminates the propagation of bad packets, enabling all of the available ndwidth to be used for valid information.

While other switching technologies such as "cut-through" or "express" impose minimal ame latency, they will also permit bad frames to propagate out to the Ethernet segments nnected. The "cut-through" technique permits collision fragment frames, which are a result of te collisions, to be forwarded to add to the network traffic. Since there is no way to filter ames with a bad CRC (the entire frame must be present in order for CRC to be calculated), the sult of indiscriminate cut-through forwarding is greater traffic congestion, especially at peak tivity. Since collisions and bad packets are more likely when traffic is heavy, the result of ore-and-forward operation is that more bandwidth is available for good packets when the traffic ad is greatest.

To minimize the possibility of dropping frames on congested ports, each Black-Box E14XXA-Series Switches dynamically allocates buffer space from an 8 MB memory pool, suring that heavily used ports receive very large buffer space for packet storage. (Many other witches have their packet buffer storage space divided evenly across all ports, resulting in a mall, fixed number of packets to be stored per port. When the port buffer fills up, dropped ckets result .) The other two LE14XXA-Series Switches LE1408A and LE1416A dynamically locates buffer from an 4MB memory pool. This dynamic buffer allocation provides the pability for the maximum resources of the LE14XXA-Series unit to be applied to all traffic ads, even when the traffic activity is unbalanced across the ports. Since the traffic on an erating network is constantly varying in packet density per port and in aggregate density, the

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Contents Modular Switches Trademarks Contacting Black Box CorporationFCC Statement Black Box Modular Switches Installation and User Guide 8/99 Table of Contents Troubleshooting Technical Specifications Performance Connectors for copper wiringFiber Multi -mode connector types Network StandardsFiber Single-mode connector types Manual switch -selections and jumpersPower Supply Internal 48VDC Power Supply OptionalWarranty Agency ApprovalsModel Information LE1401ALE1408A LE1416AIntroduction Inspecting the Package and Product Product Description , 8-port and 16-port Modular Switches LE14XXA-Series chassis modelsModular Switches Fiber 4-Port Modules, LE1420C, LE1419C LE1423C LE1422C 4-port modules, 100Mb fiber4-port modules, 10 Mb fiber 4 4-Port Module, RJ-45 copper Combo 4 Port Modules, 3 + 1, 3 RJ-45 and 1 fiber portFrame Buffering and Latency Page Plug-and-Play installation for high performance switching Front-mounted LEDs, world-wide AC power supplyFull-duplex or Half-duplex operation, auto-sensing Port, 12-port, 8-port and 4-port modelsApplications Example 1 LE1401AXample 2 8-port LE1408A 4c LE1416A provides a 100Mb mixed-media backbone Switch Example 3 16-port LE1416AInstallation Locating LE14XXA-Series SwitchesConnecting Ethernet Media Connecting Fiber Optic ST-type, twist-lockIeee Standard Media Type Max. Distance Port Module Fiber CopperConnecting Single-Mode Fiber Optic Connecting Fiber Optic S C-type, Snap-InMedia Ieee Standard Connector Table-Top or Shelf Mounting Wall or Vertical Surface Mounting, 8-port LE1401AProper mounting Magnum LE1401A, optionalFactory Settings 10/100 Mbps Factory Settings For RJ-45 Factory Settings 10Mbps Half- Duplex 10Mbps Fiber ports internal jumper settings Powering the LE14XXA-Series SwitchPage Port Module 4PM Installation Preparation for Installing and Removing 4PMsEp 2. Remove Chassis Cover Gure 3.9.1a Removing Hassis CoverScrews hold Face Plates 1c Front View 4PM RetainingInstalling 4PM Cards in the LE14XXA-Series 2b Top View 4PM Module Installed inside a LE1416A Inserting 4PM Cards Into a LE1416A4PM Cards Filtering and Forwarding Switching FunctionalityAddress Learning Power LED, on when AC power is applied to the unit Status LEDsFor all LE14XXA-Series models Steady ON, Link status for 10 Mbps and 100Mbps operationGeneral information Auto-negotiation for 10 Mb ports, half- or full-duplex mode Flow-control, Ieee 802.3x standardDistanc Module Introduction LE14XXA-Series 4-Port Modules4PM Product DescriptionIEEE-specified 100Mbps shared-collision LE1421C 100Mbps single-mode FX-S C-type, snap-in connector Small-form-factor LE1425C Twisted Pair, 10/100Mb TP 4-Port 10/100BASE-T and 100BASE-FX Combo Quad-Port Connectors 10 4PM-FP Fety, etcTroubleshooting Before Calling for AssistanceWhen Calling for Assistance Shipping and Packaging InformationBlack Box Corporation

LE14XXA, Modular Switches specifications

The Black Box LE14XXA series of modular switches are designed for high-performance networking in both small and medium enterprises, as well as in larger data center environments. These switches stand out due to their scalability, flexibility, and robust functionality, making them suitable for a variety of applications.

One of the main features of the LE14XXA modular switches is their modular design, allowing for the integration of various interface cards to tailor the switch to specific networking needs. This flexibility ensures that organizations can adapt their network architecture as requirements evolve, making it a future-proof investment. The switches support a range of modules, including Ethernet, fiber optics, and PoE (Power over Ethernet), which can be easily swapped out or added to support changing technology demands.

In terms of performance, the LE14XXA series offers impressive throughput capabilities, often supporting up to 10 Gbps per port. This speed is critical for businesses that rely on fast data transfer rates for tasks such as video conferencing, large file transfers, and real-time applications. The switches also feature advanced Layer 2 and Layer 3 functionalities, facilitating efficient data routing and switching, which is essential for maintaining effective network performance.

Security is another critical characteristic of the Black Box LE14XXA switches. They incorporate a variety of security protocols, including 802.1X port-based access control, VLAN support, and secure management interfaces, which help protect sensitive data and ensure compliance with industry standards. This makes them an excellent choice for organizations that prioritize data protection and regulatory compliance.

Ethernet redundancy protocols, such as Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP), enhance network reliability by providing failover options in case of link failures. Additionally, the LE14XXA switches feature energy-efficient designs that comply with energy-saving standards, which can significantly reduce operational costs over time.

User-friendly management interfaces, including a web-based GUI and command-line interface (CLI), simplify the configuration and monitoring processes. This ensures that IT administrators can efficiently handle the network without extensive training or experience.

Overall, the Black Box LE14XXA modular switches combine advanced technology, security features, and versatile design, making them a powerful choice for modern networking needs. Their adaptability and high performance offer businesses the capability to build scalable and secure networks that can grow alongside their operations.