Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →A Class 4 switch is an intermediate telephone-network switch, usually called a tandem switch. It routes calls between telephone offices by connecting network trunks; unlike a local end-office switch, it generally does not connect directly to individual telephones.
What a Class 4 switch does
In the public switched telephone network (PSTN), a Class 4 switch moves traffic from one network office or switch to another. A carrier-agreement template defines a tandem as a switch that “connects one trunk to another, in a series, for the purpose of exchanging traffic” and describes it as an intermediate switch between the call’s origin and destination (carrier-agreement template). Dialogic’s glossary likewise uses tandem switch for the intermediate switching role (Dialogic glossary).
As an Amazon Associate I earn from qualifying purchases.
Here, trunk means a connection between telephone-network switches or offices, rather than a subscriber’s individual phone line. Class 4 describes the switch’s place and function in the call path; it is not a particular model number or a guarantee of one hardware technology.
Where it sits in a call
A simplified call path is:
- Caller’s telephone connects to a local end office, commonly a Class 5 switch.
- If the call needs to travel between network offices, one or more Class 4 tandem switches can route it onward.
- A destination-side end office connects the call to the recipient’s telephone.
Not every call passes through a Class 4 switch. Its intermediate role matters when traffic needs to move between offices; it generally does not connect directly to customers (carrier-agreement template; technical reference).
#1 Best Overall
- 𝗢𝗻𝗲 𝗦𝘄𝗶𝘁𝗰𝗵 𝗠𝗮𝗱𝗲 𝘁𝗼 𝗘𝘅𝗽𝗮𝗻𝗱 𝗡𝗲𝘁𝘄𝗼𝗿𝗸: 5× 10/100/1000Mbps RJ45 Ports supporting Auto Negotiation and Auto MDI/MDIX.
- 𝗚𝗶𝗴𝗮𝗯𝗶𝘁 𝘁𝗵𝗮𝘁 𝗦𝗮𝘃𝗲𝘀 𝗘𝗻𝗲𝗿𝗴𝘆: Latest innovative energy-efficient technology greatly expands your network capacity with much less power consumption and helps save money.
- 𝗥𝗲𝗹𝗶𝗮𝗯𝗹𝗲 𝗮𝗻𝗱 𝗤𝘂𝗶𝗲𝘁: IEEE 802.3X flow control provides reliable data transfer and Fanless design ensures quiet operation.
- 𝗣𝗹𝘂𝗴 𝗮𝗻𝗱 𝗣𝗹𝗮𝘆: Easy setup with no software installation or configuration needed.
- 𝗔𝗱𝘃𝗮𝗻𝗰𝗲𝗱 𝗦𝗼𝗳𝘁𝘄𝗮𝗿𝗲 𝗙𝗲𝗮𝘁𝘂𝗿𝗲𝘀: Prioritize your traffic and guarantee high quality of video or voice data transmission with Port-based 802.1p/DSCP QoS and IGMP Snooping.
Class 4 vs. Class 5 switches
| Feature | Class 4 | Class 5 |
|---|---|---|
| Common name | Tandem switch | End-office switch |
| Network position | Intermediate, between network offices | Local exchange, serving subscriber lines |
| Typical role | Routes traffic between offices by connecting trunks | Provides local switching associated with subscriber lines and telephones |
| Direct connection to individual telephones | Generally no | Associated with serving subscribers |
The distinction is functional: Class 4 is the intermediate tandem role, while Class 5 is associated with the subscriber-serving end office (carrier-agreement template; technical reference). The terms do not, by themselves, specify one physical design for every switch.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Common tandem roles
Access tandem
An access tandem connects local end offices toward interexchange carriers, which provide long-distance service. It may serve traffic near a carrier’s point of presence.
Rank #2
- GIGABIT ETHERNET PORTS: Features 5 x 1.0Gbps Ethernet ports for high-speed connectivity. Auto-negotiating ports detect the optimal speed for connected devices and work with existing Cat5e or Cat6 Ethernet cables.
- PLUG-AND-PLAY UNMANAGED NETWORK SWITCH: Simple plug-and-play setup with no software to install or configuration required.
- FLEXIBLE MOUNTING OPTIONS: Compact metal design supports desktop or wall-mount placement for versatile installation.
- SILENT & ENERGY-EFFICIENT OPERATION: Fanless design ensures silent performance, while IEEE 802.3az Energy Efficient Ethernet reduces power consumption without compromising high-speed network performance.
- REGIONAL COMPATIBILITY: Made for use in U.S. & CA only
Local or sector tandem
A local or sector tandem connects end offices to exchange traffic within a local access and transport area.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errorsThese are common functional descriptions, not universal labels: terminology and network design can vary by carrier. Regulatory references to Class 4 switching may also use the term for specific purposes, such as defining telephone-service origination and termination, rather than setting out a complete engineering taxonomy (regulatory material; technical reference).
Quick Recap
Best Value
- Telephone Cable with Switch:Telephone cable with an on/off button switch, you can easily disconnect the telephone set by just pressing the switch without unplugging, avoiding many nuisance calls and giving you a quiet rest time.(Note: Please use a full 6-core telephone line, make sure the first core is connected for the switch function to work properly.)
- Easy to Use:Simple, easy to install, protects the port of the telephone to avoid constant plugging and unplugging. When you don't want to be disturbed, you can easily turn off the telephone set, making life easier and simpler
- Quality Material:Using environmentally friendly PVC sheath and shielded copper wire, exquisite workmanship, accurate signal transmission, providing a good and solid connection without signal loss
- Compatible Devices:For data/voice applications. Universally compatible with all RJ12 devices, such as landline, fax or answering machine
- Usage Scenario:Home, study, living room, bedroom, office, business meeting, education, entertainment, etc
Rank #4
- New generic 2 Ports RJ11 RJ12 Manual Sharing Switch Box, Hot-swappable (no need to reboot computer)
- 6P6C female connector, 2 manual switch buttons
- 2 Ports RJ11 RJ12 Switch Box
- High quality rotary switch,No power required No additional software needed Easy to use and install
- Cable not included**
Rank #3
- GIGABIT ETHERNET PORTS: Features 8 x 1.0Gbps Ethernet ports for high-speed connectivity. Auto-negotiating ports detect the optimal speed for connected devices and work with existing Cat5e or Cat6 Ethernet cables.
- PLUG-AND-PLAY UNMANAGED NETWORK SWITCH: Simple plug-and-play setup with no software to install or configuration required.
- FLEXIBLE MOUNTING OPTIONS: Compact metal design supports desktop or wall-mount placement for versatile installation.
- SILENT & ENERGY-EFFICIENT OPERATION: Fanless design ensures silent performance, while IEEE 802.3az Energy Efficient Ethernet reduces power consumption without compromising high-speed network performance.
- REGIONAL COMPATIBILITY: Made for use in U.S. & CA only
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
