there is support for preshared key for IKE authentication. With KB912761 for Windows XP SP2 or on Windows XP SP3, users can configure whether EFS generates a self-signed certificate when a certificate authority is unavailable. Windows Firewall beginning with Windows XP SP2 also supports IPv6 stateful filtering. Applications and tools such as the Telnet client, FTP client, ping, nslookup, tracert, DNS resolver, file and print sharing, Internet Explorer, IIS have been updated to support IPv6. Windows XP SP1 and greater support the downloadable WIA Library v2.0 which provides access to WIA functionality through programming languages and scripting environments that support OLE Automation. Service Pack 1 48-bit LBA support for ATA/ATAPI disk drives and generic drivers for UltraDMA Mode 5 and 6 support are installed. Support for and the default use of AES-256 symmetric encryption algorithm for all EFS-encrypted files was installed. EAP-TLS support, PEAPv0/EAP-MSCHAPv2 support was installed. USB 2.0 support Beginning with Windows XP Service Pack 1, generic USB 2.0 Enhanced Host Controller Interface drivers are installed. Windows XP also adds support for USB device classes such as Bluetooth, USB video device class, imaging (still image capture device class) and Media Transfer Protocol with Windows Media Player 10. For mass storage devices, Windows XP introduces hardware descriptors to distinguish between various storage types so that the operating system can set an appropriate default write caching policy. For example, for USB devices, it disables write caching by default so that surprise removal of these devices do not cause data loss. Device Manager provides a configuration setting whether to optimize devices for quick removal or for performance. FireWire (IEEE 1394) support Windows XP includes FireWire 800 support (1394b) beginning with Service Pack 1. As mentioned in the above section, Windows XP includes improved support for FireWire cameras and audio video devices. S/PDIF audio and MPEG-2 video streams are supported across FireWire from audio video receivers or set-top boxes, DVD or D-VHS, speakers, or TV transmissions. Windows XP supports the AV/C (IEC 61883 protocol for isochronous real-time data transfer for audio-video applications. Windows XP also allows non-FireWire devices to be exposed as virtual FireWire devices. Direct memory access over the 1394 bus from the host to the target allows kernel debugging over FireWire. Finally, there is support for TCP/IP networking and Internet Connection Sharing over the IEEE 1394 bus. Service Pack 2 USB block storage devices can be made read-only so writing data