GLC-LH-SM vs SFP-GE-L: What’s the Difference?

GLC-LH-SM and SFP-GE-L are two Cisco 1000BASE-LX/LH Ethernet transceivers. Due to the similar mode and performance such as supporting distance and working wavelength, users are often confused with Cisco GLC-LH-SM and SFP-GE-L when they are choosing these SFP modules. Then, what’s the difference between Cisco GLC-LH-SM and SFP-GE-L? This post intends to give a simple explanation of GLC-LH-SM vs SFP-GE-L.

GLC-LH-SM vs SFP-GE-L

Specifications of GLC-LH-SM and SFP-GE-L
GLC-LH-SM SFP Module

Cisco GLC-LH-SM is a hot-swapple optical transceiver that supports the maximum data rate of 1Gbps. It’s compatible with the IEEE 802.3z 1000BASE-LX standard, and can operate on standard single-mode fiber optic link spans of up to 10 km and up to 550 m on any multimode fibers.

Modules Interface Wavelength Tx power Receiver Sensitivity DOM Support Temperature Range
Cisco GLC-LH-SM LC duplex 1310nm -9.5 ~ -3dBm < -23dBm No 32℉to 158℉
(0℃ to 70℃)
SFP-GE-L SFP Module

SFP-GE-L transceiver has many similarities with GLC-LH-SM transceiver. It is also a Cisco 1000BASE-LX/LH Ethernet transceiver that designed for Gigabit Ethernet applications. This 1000BASE-LX/LH SFP, compatible with the IEEE 802.3z 1000BASE-LX standard, and can operate on standard single-mode fiber optic link spans of up to 10 km and up to 550 m on any multimode fibers.

Modules Interface Wavelength Tx power Receiver Sensitivity DOM Support Temperature Range
Cisco SFP-GE-L LC duplex 1310nm -9.5 ~ -3dBm < -23dBm No 23℉ to 185℉(-5℃ to 85℃)

Notes: no matter GLC-LH-SM or SFP-GE-L modules, mode conditioning patch cables are required when they are used for 1000BASE-LX/LH applications over FDDI-grade, OM1, and OM2 fiber cables.

GLC-LH-SM vs SFP-GE-L: What’s the Difference?

From the Cisco official notes, Cisco original GLC-LH-SM SFP and SFP-GE-L transceiver have been no longer for sale since March 8, 2013. But this doesn’t affect the market of these two SFP modules. Many users still choose to use them. As mentioned above, GLC-LH-SM and SFP-GE-L are easy to be confused. In fact, it’s not difficult to tell from them.

The first big difference between the two SFP modules is SFP-GE-L SFP supports DOM (digital optical monitoring) while GLC-LH-SM module doesn’t. DOM is an important function available on fiber optic transceiver. It allows users to monitor parameters of modules, such as optical output power, optical input power, temperature, laser bias current, and transceiver supply voltage, in real time, offering users more convenience when using optical modules. Another difference is the operating temperature range. The temperature range of Cisco GLC-LH-SM SFP is 32℉to 158℉(0℃ to 70℃), while the extended operating temperature range of SFP-GE-L module is 23℉ to 185℉ (-5℃ to 85℃).

GLC-LH-SM vs SFP-GE-L: Which One to Select?

From the contents above—GLC-LH-SM vs SFP-GE-L, we can draw a conclusion that GLC-LH-SM and SFP-GE-L nearly can be used as the same one type module sometimes, but their existing differences still differ them from some applications. For example, the WS-SUP32-8GE-3B does not support DOM SFP modules like the SFP-GE-L while supporting GLC-LH-SM SFP. Therefore, buying the suitable one for your devices when choosing from the two modules. As noted above, these two modules are end-of-sale in 2013. However, FS.COM provides these two modules at a cheap price. And other types of compatible optical transceivers are available too. Every optic module in FS.COM is 100% tested to ensure fully compatible. More details, please visit www.fs.com.

Compatible SFP Modules for Mikrotik CRS125-24G-1S-IN & CRS125-24G-1S-RM

Mikrotik CRS125-24G-1S series cloud router switch is available in CRS125-24G-1S-IN and CRS125-24G-1S-RM two models. It combines the best features of a fully functional router and a Layer 3 switch, is powered by the familiar RouterOS. As we know, these two models switch both have one SFP port. Then, what SFP modules can you choose for your switch? This blog will give some choices.

Overview for CRS125-24G-1S-IN and CRS125-24G-1S-RM Switch
As show in the figure below, both CRS125-24G-1S-IN and CRS125-24G-1S-RM switches have 24 RJ45 ports and 1 SFP port. One is a desktop type, and the other is a 1U rackmount type. You can according to your specific needs to choose the right one.

CRS125-24G-1S-IN CRS125-24G-1S-RM

Detailed specifications for CRS125-24G-1S and CRS125-24G-1S-RM are listed in the following table:

CPU Qualcomm Atheros AR9344 600 MHz
Memory 128MB
Ethernet 24x 10/100/1000 Mbit/s Gigabit Ethernet with Auto-MDI/X
Expansion microUSB port
Storage 128MB Onboard NAND with multiple OS partition support
Serial port One RJ45 serial port
Extras Reset switch; beeper; voltage and temperature monitoring, touchscreen LCD
Power options 8-28V, 24V 0.8A PSU included
Case dimensions 285x145x45mm
Temperature -35C to +65C tested
OS MikroTik RouterOS v6, Level 5 license
Included CRS switch, power adapter, and USB OTG cable (for 4G dongle or USB drive)

User Guide for CRS125-24G-1S-IN and CRS125-24G-1S-RM Switch
The CRS125-24G-1S and CRS125-24G-1S-RM are preinstalled with RouterOS and are ready to use. Switch is compatible with RouterOS v6 and newer, if your switch comes preinstalled with an earlier version, please upgrade before using it. For CRS125-24G-1S and CRS125-24G-1S-RM: All the ports are switched. Both models can be accessed though the IP 192.168.88.1, username is admin and there is no password. Please connect with your web browser to this IP address to configure it.

Compatible SFP Modules for CRS125-24G-1S-IN & CRS125-24G-1S-RM Switch
According to Mikrotik cloud router switch guide, CRS125-24G-1S-IN and CRS125-24G-1S-RM switches are compatible with 1.25G SFP modules. SFP+ port supports only modules up to 10KM LR (long reach). FS.COM provides a full range of compatible 1.25G SFP modules at high quality and low price, which can work well in Mikrotik switches. 1000BASE-SX SFP modules are only sold at US$  6.00. Part of the products from FS that are compatible with this Mikrotik CRS125-24G-1S-IN and CRS125-24G-1S-RM switches are listed below for your reference.

FS P/N Description
SFP-GB-GE-T Generic Compatible 1000BASE-T SFP Copper RJ-45 100m Transceiver
SFP-GB-GE-T Generic Compatible 10/100/1000BASE-T SFP Copper RJ-45 100m Transceiver
SFP1G-SX-85 Generic Compatible 1000BASE-SX SFP 850nm 550m DOM Transceiver
SFP1G-SX-31 Generic Compatible 1000BASE-SX SFP 1310nm 2km DOM Transceiver
SFP-LX Generic Compatible 1000BASE-LX/LH SFP 1310nm 10km DOM Transceiver

Compatible Optical Transceivers for Cisco Catalyst 9500 Series Switches

According to a recent survey, over half (57%) of companies have already adopted the Internet of Things (IoT) technology. By 2019, that statistic is projected to reach 85% as the expectations for IoT to deliver value and innovation continue to grow. Many advocates are struggling to secure IoT devices. To lead the pack in the switches markets, Cisco recently announced the Catalyst 9500 Series switches, which are designed for security, IoT and the cloud. The switches will be the next generation of the most widely deployed switching platform. Here in this article will take you to understand more about Catalyst 9500 switches and which optical transceivers are compatible for it.

Cisco Catalyst 9500 Series Switches

Cisco Catalyst 9500 Switches – Built for Security, IoT, and Cloud

The Cisco catalyst 9500 series switches are the next generation of enterprise-class core and aggregation layer switches, which are part of the new Cisco catalyst 9000 family. These switches come with 4-core 2.4-GHz CPU, 16-GB DDR4 memory and 16-GB internal storage. The catalyst 9500 comes in three different varieties: Catalyst 9500-24Q, Catalyst 9500-12Q and Catalyst 9500-40X. They support 10G and 40G Gigabit Ethernet network connection. The most important feature is that these switches support the advanced routing and infrastructure services, such as MPLS L2/L3 VPNs and MVPN. And they are designed for full fabric-control with Cisco DNA and Software-Defined Access (SD-Access). Therefore, these switches deliver stellar performance and functionality and extend Cisco’s networking leadership with significant innovations in security, mobility, IoT and cloud.

Model Description Total QSFP or SFP+ Ports
Catalyst 9500-24Q Cisco catalyst 9500 series 24-port 40 Gigabit Ethernet with QSFP 24 QSFP/24 SFP+
Catalyst 9500-12Q Cisco catalyst 9500 series 12-port 40 Gigabit Ethernet with QSFP (C9500-12Q-E etc) 12 QSFP/12 SFP+
Catalyst 9500-40X Cisco catalyst 9500 series 40-port 10 Gigabit Ethernet with SFP+ 40 SFP+
Software-Defined Access for Cisco Catalyst 9500 Switches

The Cisco catalyst 9500 series switches form the foundational building block for Software-Defined Access. Software-Defined Access is the industry’s first intent-based networking solution for the Enterprise built on the principles of Cisco’s Digital Network Architecture (DNA). It is an open and extensible, software-driven architecture that accelerates and simplifies your enterprise network operations. The programmable architecture frees your IT staff from time-consuming, repetitive network configuration tasks. Compared catalyst 9500 to the older switches, it performs more benefits for customers:

Cisco Catalyst 9500 Software-Defined Access

  • Reduced cost and complexity with Cisco Software-Defined Access by automating policy, enabling fast service creation and providing complete visibility into the wired and wireless access networks.
  • Create better customer and employee experiences through higher performance and improved support for mobility and new apps.
  • Advanced end-to-end security to handle threats before, during and after attacks.
Compatible QSFP+ / SFP+ Transceivers for Cisco Catalyst 9500 Switches

According to Cisco 10/40 Gigabit Ethernet Transceiver Modules Compatibility Matrix, C9500-12Q, C9500-24Q and C9500-40X can support SFP-10G-ER, SFP-10G-ZR, SFP-10G-ER-S, SFP-10G-ZR-S, QSFP-40G-SR4, QSFP-40G-LR4, SFP-40G-SR4-S ect. All SFP+ and QSFP+ transceivers can be found in FS.COM. And all of these cost-effective compatible modules have been strictly tested to make sure 100% compatibility.

QSFP+ Transceivers
Transceiver Model Part ID Transceiver Description
QSFP-40G-SR4 36157 Cisco QSFP-40G-SR4 Compatible 40GBASE-SR4 QSFP+ 850nm 150m MTP/MPO DOM Transceiver, $ 49.00
QSFP-40G-CSR4 36165 Cisco QSFP-40G-CSR4 Compatible 40GBASE-CSR4 QSFP+ 850nm 400m MTP/MPO DOM Transceiver, $ 59.00
QSFP-40G-SR4-S 36143 Cisco QSFP-40G-SR4-S Compatible 40GBASE-SR4 QSFP+ 850nm 150m MTP/MPO DOM Transceiver, $ 49.00
QSFP-40G-LR4 36170 Cisco QSFP-40G-LR4 Compatible 40GBASE-LR4 and OTU3 QSFP+ 1310nm 10km LC DOM Transceiver, $ 340.00
QSFP-40G-LR4-S 36153 Cisco QSFP-40G-LR4-S Compatible 40GBASE-LR4 QSFP+ 1310nm 10km LC DOM Transceiver, $ 340.00
QSFP-40G-ER4 36173 Cisco QSFP-40G-ER4 Compatible 40GBASE-ER4 and OTU3 QSFP+ 1310nm 40km LC DOM Transceiver, $ 1,500.00
QSFP-40G-SR-BD 48722 Cisco QSFP-40G-SR-BD Compatible 40GBASE-SR Bi-Directional Duplex LC Transceiver, $ 300.00
WSP-Q40GLR4L
(except C9500-40X )
36172 Cisco WSP-Q40GLR4L Compatible 40GBASE-LR4L QSFP+ 1310nm 2km LC DOM Transceiver, $ 340.00
SFP+ Transceivers
Transceiver Model Part ID Transceiver Description
SFP-10G-SR 11552 Cisco SFP-10G-SR Compatible 10GBASE-SR SFP+ 850nm 300m DOM Transceiver, $ 16.00
SFP-10G-SR-S 36433 Cisco SFP-10G-SR-S Compatible 10GBASE-SR SFP+ 850nm 300m DOM Transceiver, $ 16.00
SFP-10G-LR 11555 Cisco SFP-10G-LR Compatible 10GBASE-LR SFP+ 1310nm 10km DOM Transceiver,$ 34.00
SFP-10G-LR-S 36434 Cisco SFP-10G-LR-S Compatible 10GBASE-LR SFP+ 1310nm 10km DOM Transceive, $ 34.00
SFP-10G-LRM
(except C9500-24Q / C9500-12Q )
11556 Cisco SFP-10G-LRM Compatible 10GBASE-LRM SFP+ 1310nm 220m DOM Transceiver, $ 34.00
SFP-10G-ER 11557 Cisco SFP-10G-ER Compatible 10GBASE-ER SFP+ 1550nm 40km DOM Transceiver, $ 149.00
SFP-10G-ER-S 36435 Cisco SFP-10G-ER-S Compatible 10GBASE-ER SFP+ 1550nm 40km DOM Transceiver, $ 149.00
SFP-10G-ZR 11582 Cisco SFP-10G-ZR Compatible 10GBASE-ZR/ZW and OTU2e SFP+ 1550nm 80km DOM Transceiver,$ 299.00
SFP-10G-ZR-S 36436 Cisco SFP-10G-ZR-S Compatible 10GBASE-ZR/ZW and OTU2e SFP+ 1550nm 80km DOM Transceiver,$ 299.00

Note: For C9500-24Q / C9500-12Q, the Transceivers should be used with CVR-QSFP-SFP10G.

Conclusion

The catalyst 9500 switches solve some persistent challenges of enterprise networks by utilizing platform innovations built around four key areas: security, Internet of Things (IoT) convergence, mobility and cloud readiness. There is no doubt that catalyst 9500 is leading us to a new era of faster and securer network. And if you need any transceiver for Cisco catalyst 9500 series, please contact us via www.fs.com. All the products offered by FS.COM are tested before shipping to ensure superior quality.

Can A Computer Connected to the PoE Switch?

PoE switches are commonly used in various networks. It can be low-cost unmanaged edge switches with a few ports or complex multi-port rack-mounted units with sophisticated management. When used in small or home networks, many people may wonder if it can be connected directly with a computer. This post will discuss this question in details.

What Are PoE and PoE Switch

Before the discussion, it is necessary to have a basic understand of what are PoE and PoE Switch:

PoE

As demands for connection from networking devices such as IP phones, IP cameras and access points increase, deployment complexity and cost rise as well. For less cable usage and investment, Power over Ethernet (PoE) technology is developed to provide both data connection and electrical power to devices through just one Cat5/Cat5e/Cat6 cable.

PoE Switch

PoE switch is a network switch that has Power over Ethernet injection built-in, which can transmit both power and data through an Cat5/Cat5e/Cat6 Ethernet cable at the same time. This kind of switch makes it easy for different sectors to deploy powered devices like VoIP phones, wireless access points and IP surveillance cameras in challenging places like ceilings, walls, outdoors, or wherever electrical outlets are not easily available.

poe switch connection

Can A Computer Connected Directly to the PoE Switch?

As shown below,PoE switch usually have the same RJ45 port as a computer. So many people will think they can be connected directly. But do not forget that PoE switch may also transmit electrical power through the RJ45 port and Cat5/Cat5e/Cat6 cable to the computer. Then can a computer be connected directly to the PoE switch? This is largely depend on the switch you have:

poe switch

If you have a PoE switch that conforms to 802.3af (the PoE standard) or 802.3at (the PoE Plus standard) and doesn’t claim to be “passive”, you can definitely connect your computer with it. This is because this kind of PoE switch has the function of PoE detection which is designed to avoid damage to non-PoE devices. In other words, when you connect other network devices to your PoE switch, it will communicate with the these devices whether they need power or not. Power is only injected if and when this negotiation is successful. Ethernet devices such as phones and access points are detected by the switch as accepting PoE and will receive the additional power feature from the PoE switch/port. Whereas a computer and other non-PoE devices will not be detected as having PoE capability and will just use the data communications features of the port.

computer connect to poe switch

However, there exists a class of PoE switches, usually referred to as “passive” or “always on”, which supply power without PoE detection. Why would anyone do this? Because this kind of PoE switch is significantly cheaper. Whether it damages your device depends on the voltage of the passive PoE switch and your devices. For a computer, it may be damaged for excessive voltage or current.

Conclusion

PoE switch is a dedicated device that contains multiple Ethernet ports to provide power and network communications. It is usually used in NVR/IP camera networks. For small or home networks, if you want to connect a computer to the PoE switch, make sure your switch follows the standard 802.3af or 802.3at PoE requirements. So can you connect a computer directly to your PoE switch?

How to Light a DWDM Ring Beyond 10G?

Network layout nowadays is no longer limited by old rules created for early Ethernet networks. The technology and infrastructure devices available currently allows for different network topologies, including bus, star, ring and mesh networks. Each of them has its benefits and drawbacks and can be combined to suit application needs. This article emphasizes on the DWDM ring network configuration, illustrating the approaches to build a fiber ring beyond 10G.

What Is a DWDM Fiber Ring?

A fiber ring refers to the network topology in which each node connects to exactly two other nodes, forming a single continuous pathway for signals through each node. A ring configuration is designed to withstand a single failure. If there happens to be a failure, the system automatically reconfigure itself.

Similarly, a DWDM ring network includes a fiber in a ring configuration that fully interconnects nodes. Two fiber rings are even presented in some systems for network protection. This ring DWDM topology is commonly adopted in a local or a metropolitan area which can span a few tens of kilometers. Many wavelength channels and nodes may be involved in DWDM ring system. One of the nodes in the ring is a hub station where all wavelengths are sourced, terminated, and managed, connectivity with other networks takes place at this hub station. Each node and the hub have optical add-drop multiplexers (OADM) to drop off and add one or more designated wavelength channels. As the number of OADMs increases, signal loss occurs and optical amplifier is needed.

DWDM ring

How to Create a DWDM Fiber Ring Beyond 10G?

Assuming to build a higher than 10G optical ring using two strands of dark fibers, all nodes in this ring configuration are less than 10km apart and there are 8 nodes in total. Here we illustrate the options for achieving a DWDM ring beyond 10G.

20G Fiber Ring

For a 20G ring, the configuration is rather simple. There is no need for an OADM or Mux/Demux, it is recommend to use an Ethernet switch with two SFP+ ports and a pair of BIDI SFP+ optics.

Items Description
S5800-48F4S High Performance Data Center Switch (48*1GE+4*10GE)
10GBASE-BX SFP+ Generic Compatible 10GBASE-BX SFP+ 1270nm-TX/1330nm-RX 10km DOM Transceiver
10GBASE-BX SFP+ Generic Compatible 10GBASE-BX SFP+ 1330nm-TX/ 1270nm-RX 10km DOM Transceiver
40G Fiber Ring

There are three options for creating a 40G DWDM ring.

1. Use a switch with QSFP+ ports, and using QSFP+ optics in accordance. This can be the most cost-effective option for 40G if you have no future plan for more than 40G on the ring.

Items Description
S5850-48S6Q High Performance Data Center Switch (48*10GE+6*40GE)
40GBASE-LR4 Generic Compatible 40GBASE-LR4 and OTU3 QSFP+ 1310nm 10km LC Transceiver for SMF

2. Use four 10G SFP+ optics and a CWDM OADM. You could even scale up to 18 channels giving you a 180G ring if you were use all 18 CWDM channels and had that large of a OADM or Mux/Demux. First four channels with lower cost SFP+ optics, wavelength 1270nm through 1310nm. Then the next 14 channels 1350nm to 1610nm adopts SFP+ with relatively higher cost. You would need a SFP+ port per channel on both ends, and a passive CWDM OADM.

Items Description
CWDM OADM Single Fiber/ Dual Fiber CWDM OADM, East and West
10GBASE-LR SFP+ Generic Compatible 10GBASE-LR SFP+ 1310nm 10km DOM Transceiver
10GBASE-ER SFP+ Generic Compatible 10GBASE-ER SFP+ 1550nm 40km DOM Transceiver

3. Use 10G DWDM SFP+ optics and a DWDM OADM. You can choose less expensive 100Ghz optics that have up to 40 or 44 channels, or the expensive 50Ghz optics that can reach up to 80 or 88 channels.

Items Description
DWDM OADM Single Fiber/ Dual Fiber DWDM OADM, East and West
10G DWDM SFP+ Generic C40 Compatible 10G DWDM SFP+ 100GHz 1545.32nm 40km DOM Transceiver
10G DWDM SFP+ Generic H50 Compatible 10G DWDM SFP+ 50GHz 1537nm 40km DOM Transceiver
100G Fiber Ring

As for a 100G fiber ring, you can count on Ethernet switches that have 100G QSFP28 uplink ports, along with 100G QSFP28 optics. This would allow a 100G connection each way around the ring.

Items Description
S5850-48S2Q4C Carrier Grade 100G-uplink Switch (48*10GE + 2*40GE + 4*100GE)
100GBASE-LR4 Generic Compatible QSFP28 100GBASE-LR4 1310nm 10km Transceiver
Conclusion

Fiber ring enables more reliability and survivability: if a single link failure should occur – the traffic can simply be sent the other way around the ring. With the pervasiveness of Ethernet technology, the ring architecture is widely adopted to construct a Metropolitan Area Network (MAN), Metro-Ethernet service and school district that uses municipal fiber pathways. Several options for creating fiber ring beyond 10G are presented, along with the optical components needed. Hope this could be informative enough.