Implementing Firewalls for Additional Security
To further secure your wired network from wireless users, implement a firewall between the access point and your wired network, as shown in . Instead of using filters on your access point you can offload their function and allow for better inspection, auditing, and accounting by installing a separate firewall.Public Secure Packet Forwarding (PSPF) prevents wireless clients associated withan access point from communicating and sharing files between other clients connected to the same access point.This configuration can be useful in public access-deployed WLANs like airports and schools where you would want to restrict access between individual users. Figure 7.14 shows user1 restricted from accessing user2. Because PSPF is enabled, the access point will not allow such communication between individual clients to take place. If using more than one access point on the same WLAN, in order to make sure a client from AP-A cannot communicate with a client from AP-B, you need to prevent both access points from communicating with each other across your wired network. PSPF only works on unique access points.To prevent the same LAN access points from communicating between each other on the wired network, you need to apply port access lists on compatible Cisco switches interconnecting the two access points, or use protected port settings to restrict communication between ports. PSPF can be configured under radio interface
Public Secure Packet ForwardingFiltersFilters allow or restrict specific communication through an access point’s Ethernet port or radio ports. Cisco WLAN devices support MAC, IP, and Ethernet-type filters. IP filters can be configured to disallow a Telnet or HTTP Web administrator access into their access point from wireless clients. IP HTTP filters can be configured to restrict administrators-only connectivity into an access point.MAC filters can be used to authenticate and restrict access to specific network client adapters. You can also use filters for services such as Quality of Service (QOS) to group different communication types into separate QOS policies.
Radio-Frequency Identification.
RFID stands for Radio-Frequency Identification. The short form refers to tiny electronic devices that consist of a small chip and an transmitter. The chip typically is competent of carrying 2,000 bytes of data or less.
The RFID device serves the same principle as a bar code or an alluring strip on the back of a credit card or ATM card; it provides a unique identifier for that object. And, just as a bar code or magnetic strip must be scanned to get the in sequence, the RFID piece of equipment must be scanned to repossess the identifying in sequence.
RFID Works Better Than Barcodes
A noteworthy gain of RFID devices over the others mentioned higher than is that the RFID piece of tools does not need to be to be found in particular relative to the scanner. We're all familiar with the involvedness that store checkout clerks sometimes have in making sure that a barcode can be read. And noticeably, credit cards and ATM cards must be swiped through an unusual reader.
In contrast, RFID diplomacy will work within a few feet (up to 20 feet for high-frequency devices) of the scanner. For example, you could just put all of your groceries or purchases in a bag, and set the bag on the scanner. It would be able to query all of the RFID devices and total your purchase straight away. (Read a more detailed piece on RFID compared to barcodes.)
RFID technology has been on hand for more than fifty years. It has only been freshly that the ability to assemble the RFID devices has fallen to the point where they can be old as a "passing" inventory or control device. Alien technology recently sold 500 million RFID tags to Gillette at a cost of on ten cents per tag.
One reason that it has taken so long for RFID to come into familiar use is the lack of standards in the industry. Most companies invested in RFID technology only use the tags to track items within their control; many of the benefits of RFID come when items are tracked from company to company or on or after country to sovereignty.
Common Problems with RFID
Some common troubles with RFID are reader collision and tag collision. Reader collision occurs as the signals from two or more readers overlap. The tag is unable to respond to synchronized queries. Systems must be with awareness set up to avoid this problem. Tag impact occurs when many tags are in attendance in a small area; but since the read time is very fast, it is easier for vendors to develop systems that ensure that tags take action one at a time. See Problems with RFID for more in sequence.
