Adder Technology AdderLink IP manual Ports, Security issues with ports, Router/firewall address

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Ports

If you accept the analogy of IP addresses being rather like telephone numbers, then think of ports as extension numbers. In a company of any size, you generally wouldn’t expect the accounts department to share the same telephone with the technical department. Although their calls may all be related to the same company, they concern very different aspects of that company.

It is the same with IP network connections. Although you have only one network link into your computer and only one IP address (phone number), you are probably performing many different tasks through that one link, often at the same time. Thus, when you browse the web your outgoing requests and the incoming information are all channelled through port 80. When you send an email, it travels through port 25 and when you transfer files you are, without knowing it, using port 20.

At the “border crossing” between the wider Internet and every local network attached to it, there is router that is usually combined with a firewall. One of its main tasks is to direct incoming traffic to the correct place within its local network. A key piece of information to help it do this is the port number:

User accesses the company

Internet

User with VNC viewer accesses

IP address: 129.7.1.10 (this

website at: 129.7.1.10 (this

 

 

automatically uses port 5900).

automatically uses port 80).

 

 

 

 

 

Router/firewall address: 129.7.1.10

 

 

Router is programmed to send port 5900

 

 

VNC traffic to local address 192.168.0.3

 

 

and port 80 web traffic to local address

 

 

192.168.0.42

 

Web server

AdderLink IP has the local

Web server has the local

IP address: 192.168.0.3

IP address: 192.168.0.42

Security issues with ports

The settings of port numbers become important when the AdderLink IP is situated behind a network firewall. In order for a remote VNC viewer or web browser to make contact with your AdderLink IP, it is necessary for the firewall to allow communication through a particular numbered port to occur.

One specific function of firewalls is to restrict access to ports in order to prevent malicious attackers using them as a route into your network. Every new port that is opened offers a new possibility for hackers and so the number of accessible ports is purposefully kept to a minimum. In such cases, it may be advantageous to change one or both AdderLink IP ports to use the same number. The other alternative is to place the AdderLink IP unit outside the firewall and take full advantage of its secure operation features – see Networking issues for details.

IMPORTANT: The correct configuration of routers and firewalls requires advanced networking skills and intimate knowledge of the particular network. Adder Technology cannot provide specific advice on how to configure your network devices and strongly recommend that such tasks are carried out by a qualified professional.

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Contents  AdderLink IPContents Index Local user Four simultaneous remote usersModem/ISDN port IP network/InternetAdderView IP features front and rear     What’s in the box What you may additionally needSingle unit rack brackets MountingDouble unit rack brackets  Connections Host computer or KVM switchIP network port Local keyboard, video monitor and mouseTo connect a local keyboard, video monitor and mouse To connect the IP network portTo connect the power supply Power supply connectionModem/ISDN port To connect a modem or Isdn portTo connect and address the switch boxes Power control portPart 1 Local configuration Initial configurationPart 1 Local configuration Part 2 Remote configurationAdmin password To perform the initial local configurationTime and Date EncryptionAdderLink IP encryption settings Encryption settingsViewer encryption settings EncryptionTo restore mouse operation when hot plugging Which restore setting do I use?Hot plugging and mouse restoration Recognising an IntelliMouse-style mouseAdderLink IP asks for an unknown admin password Resetting the configurationTo invoke a configuration reset by switch AdderLink IP does not display the configuration sequenceTo perform the remote configuration Part 2 Remote configurationPort settings Networking issuesPositioning AdderLink IP in the network Placing AdderLink IP behind a firewallTo discover a DHCP-allocated IP address AddressingDNS addressing Firewall/router addressPlacing AdderLink IP alongside the firewall Ensuring sufficient securityPorts Power control sequences Power switching configurationTo configure the power sequences for each host computer To control two or more ports simultaneouslyTo perform a flash upgrade Performing a flash upgradeConfigure network option Important Wait until the upgrade is completeLocal connection Connecting to the AdderLink IPTo make a local connection To view the local control menuTo avoid the ‘hall of mirrors’ effect Remote connectionsTo connect using your Web browser To connect using the VNC viewerRemote connection by VNC viewer Remote connection by Web browserUsing the viewer window When using the viewer windowMenu bar Mouse pointers ConfigureHost selection To select a hostPower control Access mode shared/privateAuto calibrate Re-synchronise mouseControls Phase Setting the Threshold manuallyContrast  Connecting via dial up modem or Isdn link Downloading VNC viewer from the AdderLink IPIf you need to enter a port number Supported web browsers Viewer encryption settingsWindows LinuxWhen logging on using VNC viewer, I cannot enter a username TroubleshootingGetting assistance US +1 888 275To access the local configuration menus Appendix 1 Local configuration menusUnit configuration Network configuration Modem configuration To reset the AdderLink IP configuration Reset configurationClear IP access control What is IP access control?To clear IP access control Colour/Encoding Appendix 2 VNC viewer connection optionsAuto select Preferred encodingMisc InputsReload defaults DefaultsSave as defaults Save configuration file asAppendix 3 VNC viewer window options Appendix 4 Browser viewer options Encoding and colour levelSecurity Appendix 5 Remote configuration menus To access the remote configuration menusMain configuration menu Logged on users User accounts Hardware Version Screensaver timeoutFirmware Version Host Keyboard LayoutIdle timeout Advanced unit configurationProtocol timeout Force VNC protocolIP access control IP network maskIP gateway To define a new IP access control entry Setting IP access controlTo reorder access control entries To edit/remove access control entriesSerial port configuration Power control portModem port To create a new host entry Host configurationTo copy and paste the log Logging and statusOccurred Click to clear All log entries Refresh ListAppendix 6 Addresses, masks and ports IP addressesNet masks Inside a bit-wise and function Net masks the binary explanationBinary equivalent Binary octet afterSingle locations Calculating the mask for IP access controlAll locations Address rangesSecurity issues with ports PortsRouter/firewall address Appendix 7 Cable and connector specifications AdderLink IP to power switch cableRS232 serial mouse to PS/2 converter cable Appendix 8 Hotkey sequence codes Warranty Safety informationOther products in the Adder range Radio Frequency Energy European EMC directive 89/336/EECFCC Compliance Statement United States United States of America Index 

AdderLink IP specifications

Adder Technology's AdderLink IP is a cutting-edge solution designed to extend and manage KVM (Keyboard, Video, Mouse) signals over IP networks. This innovative technology facilitates the remote access and control of computers and servers, making it an essential tool for organizations that require efficient management of their IT resources.

One of the main features of AdderLink IP is its ability to transmit high-resolution video signals with minimal latency. Supporting resolutions up to 4K at 60Hz, it ensures that users experience clarity and responsiveness that is comparable to direct connections. This capability is crucial for industries such as broadcasting, media production, and any environment where graphics-intensive applications are commonplace.

The AdderLink IP employs advanced digitization techniques to ensure high-quality video transmission over standard IP networks. Its use of H.264 video compression allows for efficient bandwidth usage while maintaining image integrity. With this feature, users can easily adapt to various network conditions without compromising performance.

Another standout characteristic is the support for real-time remote access through a web browser, allowing users to connect to their systems from virtually anywhere in the world. Whether for troubleshooting, maintenance, or system management, the AdderLink IP empowers IT professionals with the flexibility they need to perform their duties effectively. The built-in security protocols ensure that access is both secure and reliable.

Moreover, AdderLink IP is designed to be user-friendly. Configuration and management can be performed via an intuitive web interface, simplifying the setup process for users of all technical skill levels. Compatibility with a range of operating systems and devices further enhances its versatility.

Furthermore, the system supports multi-user access, enabling multiple operators to connect to the same devices simultaneously without conflicts. This functionality is particularly useful in collaborative environments where teams need concurrent access to critical systems.

In summary, Adder Technology's AdderLink IP stands out as a robust solution for KVM over IP needs. With its high-quality video transmission, real-time remote access, ease of use, and enhanced security features, it enables organizations to effectively manage their IT infrastructure, thereby boosting productivity and operational efficiency. As the demand for remote access increases, AdderLink IP remains a pivotal component in the evolution of IT management solutions.