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D-Link FAQ => ShareCenter FAQs => Topic started by: JavaLawyer on February 13, 2014, 06:43:47 AM

Title: DNS ShareCenter - Should I Use DHCP, Static IP, or Reserved IP Address?
Post by: JavaLawyer on February 13, 2014, 06:43:47 AM

The protocol a D-Link ShareCenter uses to connect to a router may cause issues if not properly configured. This FAQ entry describes the different ways a D-Link ShareCenter can connect to a network and the pros and cons of each approach.

1. Basic Definitions

• DHCP - DHCP is the default configuration a new D-Link ShareCenter is configured for out-of-the-box. Using DHCP, when the ShareCenter connects to a router, the router will assign an IP address to the ShareCenter that falls within the valid IP address range defined for the router
  
• Reserved IP - Reserving an IP address is configured from the host router web UI (not the ShareCenter). Using this option, the end-user selects a specific IP address for the ShareCenter and reserves the IP address in the router. The reserved IP address will always be made available for the ShareCenter, even if the camera disconnects/reconnects to the network
  
• Static IP - A static IP address is configured in the client ShareCenter web UI (not the router). A static IP address forces the router to assign a specific IP address to the ShareCenter each and every time the ShareCenter connects to the router. The address is called static because the client device will always request the same IP address regardless of the router or network the client device is connected to
  
  

2. DHCP - Dynamic Host Configuration Protocol

DHCP is the default configuration a new D-Link ShareCenter is configured for out-of-the-box. Using DHCP, when the ShareCenter connects to a router, the router will assign an IP address to the ShareCenter that falls within the valid IP address range defined for the router.

DHCP IP address assignment rules:

• IP addresses are assigned by the router either randomly or using a set of rules built into the router
• IP addresses are assigned within the valid IP address range defined for the router. If a router is configured with the IP address range of 192.168.0.1 to 192.168.0.10, then the router may assign the IP address 192.168.0.x, where x is a value between 1 and 10
  
• The IP address 192.168.0.1 is typically reserved for the router itself and is therefore not available for other devices to use
  
• Since the DHCP protocol assigns IP addresses either randomly or using a set of rules, the ShareCenter IP address is subject to change every time the ShareCenter disconnects/reconnects to the network
  

Sample scenario:

• Assume a router is configured with the IP address range of 192.168.0.1 to 192.168.0.10
  
• When the ShareCenter attempts to connect with the router, the router assigns the IP address 192.168.0.5 (which falls within the range of 1 to 10)
  
• If the ShareCenter disconnects/reconnects from the network, the router assigns a new IP address, 192.168.1.9
  
  

3. Reserving an IP Address

Reserving an IP address is configured from the router web UI (not the ShareCenter). Using this option, the end-user selects a specific IP address for the ShareCenter and reserves the IP address in the router. The reserved IP address will always be made available for the ShareCenter, even if the ShareCenter disconnects/reconnects to the network.

Reserved IP address rules:

• IP address reservations are made from within the router (not the ShareCenter)
• When using IP address reservations, the ShareCenter should be configured to DHCP
• The reserved IP address should stay within the valid IP address range defined for the router. If a router is configured with the IP address range of 192.168.0.1 to 192.168.0.10, then the end-user may reserve the IP address 192.168.0.x, where x is a value between 2 and 10 (the value 1 is typically reserved for the router itself)
  
• A reserved IP address is associated to the MAC address of the ShareCenter
• Once and IP address is reserved to a specific ShareCenter, only that ShareCenter can use the IP address. Other network devices cannot use the IP address
  

Sample scenario:

• Assume a router is configured with the IP address range of 192.168.0.1 to 192.168.0.10
  
• The IP address 192.168.0.5 is reserved for the ShareCenter (saved in the router web UI)
  
• When the ShareCenter attempts to connect with the router, the router assigns the IP address 192.168.0.5
  
• If the ShareCenter disconnects/reconnects from the network, the router assigns the IP address, 192.168.1.5
  
  

4. Static IP Address

A static IP address is configured in the D-Link ShareCenter web UI (not the router). A static IP address forces the router to assign a specific IP address to the ShareCenter each and every time the ShareCenter connects to the router. However, there are circumstances where the router may not be able to provide the IP address requested by the ShareCenter.

Static IP address rules:

• IP address reservations are made from within the ShareCenter (not the router)
• The static IP address should stay within the valid IP address range defined for the router. If a router is configured with the IP address range of 192.168.0.1 to 192.168.0.10, then the end-user may select a static IP address of 192.168.0.x, where x is a value between 2 and 10 (the value 1 is typically reserved for the router itself)
  
• Setting a static IP address in the ShareCenter forces the router to give the IP address to the ShareCenter, even if another device is currently using the same IP address
• Every time the ShareCenter disconnects/reconnects to the network, the ShareCenter will request the same IP address
  

Sample scenario:

• ShareCenter is configured with the static IP address 192.168.0.5
  
• ShareCenter joins the network using IP address 192.168.0.5
  
• ShareCenter briefly loses power and drops from the network
• Router releases the IP address (since the ShareCenter is no longer using it)
• Laptop joins the network
• Router assigns the laptop the next free IP address: 192.168.0.5
  
• ShareCenter tries to re-joins the network using IP address: 192.168.0.5
  
• ShareCenter and laptop experience an IP address conflict

5. Best Approach: Reserved IP Address

• IP Address reservations are the preferred and safest method to manage D-Link ShareCenter connectivity
• The router (as the brains of the network) should be permitted to manage the IP addresses of all devices connected to the network, a task the router was designed to perform. This approach ensures centralized IP address management and minimizes the possibility of network issues and conflicts.
• Using pure DHCP will result in ShareCenters changing IP addresses, resulting in potential access issues if specific IP addresses are bookmarked in a browser or port forwarding is utilized
• Since the router doesn't manage static IP addresses, using pure static IP addresses may result in IP address conflict and connectivity issues if multiple network devices are competing for the same IP address

Additional Resources

• Network Cameras - Searchable FAQ Index (http://forums.dlink.com/index.php?topic=58404.0)
  
• Network Cameras - Important Posts & Information (http://forums.dlink.com/index.php?topic=58121.0)