特殊MAC地址---官方保留

IEEE Std 802.1D and IEEE Std 802.1Q Reserved Addresses

Group MAC address value	Organization using the value	Standard using the value	Notes
01-80-C2-00-00-00	IEEE 802	IEEE Std 802.1D IEEE Std 802.1Q	IEEE Std 802.1D Bridge Group Address
01-80-C2-00-00-01	IEEE 802	"	IEEE MAC-specific control protocols
01-80-C2-00-00-02	IEEE 802	"	IEEE Std 802.3 Slow Protocols multicast address
01-80-C2-00-00-03	IEEE 802	"	IEEE Std 802.1X PAE address
01-80-C2-00-00-04	IEEE 802	"	IEEE MAC-specific control protocols
01-80-C2-00-00-05	IEEE 802	"	Reserved for media access method specific use
01-80-C2-00-00-06	IEEE 802	"	Reserved for future standardization
01-80-C2-00-00-07	IEEE 802	"	Reserved for future standardization
01-80-C2-00-00-08	IEEE 802	"	Provider Bridge group address
01-80-C2-00-00-09	IEEE 802	"	Reserved for future standardization
01-80-C2-00-00-0A	IEEE 802	"	Reserved for future standardization
01-80-C2-00-00-0B	IEEE 802	"	Reserved for future standardization
01-80-C2-00-00-0C	IEEE 802	"	Reserved for future standardization
01-80-C2-00-00-0D	IEEE 802	"	Provider Bridge MVRP address
01-80-C2-00-00-0E	IEEE 802	"	Std 802.1AB Link Layer Discovery Protocol address
01-80-C2-00-00-0F	IEEE 802	"	Reserved for future standardization

Standard Group MAC Addresses

Group MAC address value	Organization using the value	Standard using the value	Notes
01-80-C2-00-00-10	IEEE 802	IEEE Std 802.1D	All LANs Bridge Management Group Address (deprectated)
01-80-C2-00-00-11	IEEE 802	IEEE Std 802.1E	Load Server Generic Address
01-80-C2-00-00-12	IEEE 802	IEEE Std 802.1E	Loadable Device Generic Address
01-80-C2-00-00-13	unassigned
01-80-C2-00-00-14	ISO/IEC JTC1/SC6	ISO/IEC 10589	All Level 1 Intermediate Systems Address
01-80-C2-00-00-15	ISO/IEC JTC1/SC6	ISO/IEC 10589	All Level 2 Intermediate Systems Address
01-80-C2-00-00-16	ISO/IEC JTC1/SC6	ISO/IEC 10030	All CONS End Systems Address
01-80-C2-00-00-17	ISO/IEC JTC1/SC6	ISO/IEC 10030	All CONS SNARES Address
01-80-C2-00-00-18	IEEE 802	IEEE Std 802.1B	Generic Address for All Manager Stations
01-80-C2-00-00-19	unassigned
01-80-C2-00-00-1A	IEEE 802	IEEE Std 802.1B	Generic Address for All Agent Stations
01-80-C2-00-00-1B	ISO/IEC JTC1/SC6	ISO/IEC 9542	All Multicast Capable End Systems Address
01-80-C2-00-00-1C	ISO/IEC JTC1/SC6	ISO/IEC 9542	All Multicast Announcements Address
01-80-C2-00-00-1D	ISO/IEC JTC1/SC6	ISO/IEC 9542	All Multicast Capable Intermediate Systems Address
01-80-C2-00-00-1E	ISO/IEC JTC1/SC6	ISO/IEC 8802-5	All DTR Concentrators MAC Group Address
01-80-C2-00-00-1F	unassigned
01-80-C2-00-00-20 — 01-80-C2-00-00-2F	IEEE 802	IEEE Std 802.1Q	Reserved for use by Multiple Registration Protocol (MRP) applications

01-80-C2-00-00-30 — 01-80-C2-00-00-3F	IEEE 802	IEEE Std 802.1ag	Destination group MAC addresses for CCM and Linktrace messages
01-80-C2-00-00-40 to 01-80-C2-00-00-4F	IETF	TRILL	Group MAC addresses used by the TRILL protocols
01-80-C2-00-00-40 — 01-80-C2-00-00-FF	unassigned
01-80-C2-00-01-00		ISO/IEC 9314-6	Ring Management Directed Beacon Multicast Address
01-80-C2-00-01-01 — 01-80-C2-00-01-0F	ISO/IEC JTC1/SC25		Assigned to ISO/IEC JTC1/SC25 for future use
01-80-C2-00-01-10	ISO/IEC JTC1/SC25	ISO/IEC 9314-6	Status Report Frame Status Report Protocol Multicast Address
01-80-C2-00-01-11 — 01-80-C2-00-01-1F	ISO/IEC JTC1/SC25		Assigned to ISO/IEC JTC1/SC25 for future use
01-80-C2-00-01-20	ISO/IEC JTC1/SC25	ISO/IEC 9314-2	All FDDI Concentrator MACs
01-80-C2-00-01-21 — 01-80-C2-00-01-2F	ISO/IEC JTC1/SC25		Assigned to ISO/IEC JTC1/SC25 for future use
01-80-C2-00-01-30	ISO/IEC JTC1/SC25	ISO/IEC 9314-6	Synchronous Bandwidth Allocation Address
01-80-C2-00-01-31 — 01-80-C2-00-01-FF	ISO/IEC JTC1/SC25		Assigned to ISO/IEC JTC1/SC25 for future use
01-80-C2-00-02-00 — 01-80-C2-00-02-FF	ETSI		Assigned to ETSI for future use
01-80-C2-00-03-00 — 01-80-C2-FF-FF-FF	unassigned

Group MAC Addresses Used in ISO 9542 ES-IS Protocol

Group MAC address value	Organization using the value	Standard using the value	Notes
09-00-2B-00-00-04	ISO/IEC JTC1/SC6	ISO 9542	All End System Network Entities Address
09-00-2B-00-00-05	ISO/IEC JTC1/SC6	ISO 9542	All Intermediate System Network Entities Address

Locally Administered Group MAC Addresses Used by IEEE Std 802.5
(IEEE Std 802.5 Functional Addresses)

Group MAC address value	Organization using the value	Standard using the value	Notes
03-00-00-00-00-08	IEEE 802	IEEE Std 802.5	Configuration Report Server (CRS) MAC Group Address
03-00-00-00-00-10	IEEE 802	IEEE Std 802.5	Ring Error Monitor (REM) MAC Group Address
03-00-00-00-00-40	IEEE 802	IEEE Std 802.5	Ring Parameter Server (RPS) MAC Group Address
03-00-00-00-01-00	IEEE 802	ISO 9542	All Intermediate System Network Entities Address
03-00-00-00-02-00	ISO/IEC JTC1/SC6, IEEE 802	ISO 9542, and IEEE Std 802.5	All End System Network Entities Address, and Lobe Media Test (LMT) MAC Group Address
03-00-00-00-04-00	IEEE 802	IEEE Std 802.1B	Generic Address for all Manager Stations
03-00-00-00-08-00	IEEE 802	ISO/IEC 10030	All CONs SNARES Address
03-00-00-00-10-00	IEEE 802	ISO/IEC 10030	All CONs End System Address
03-00-00-00-20-00	IEEE 802	IEEE Std 802.1E	Loadable Device Generic Address
03-00-00-00-40-00	IEEE 802	IEEE Std 802.1E	Load Server Generic Address
03-00-00-40-00-00	IEEE 802	IEEE Std 802.1B	Generic Address for all Agent Stations

Raspberri-Pi Debian Tuning

Speedup CPU:
we can easily modify the cpu work frequency modifying the config.txt file. Just edit /boot/config.txt
arm_freq=900
i always use this hack and my rpi run without problem
Change scheduler/elevator at boot time:
we use more responsive/less disk io usage scheduler:
modify the /boot/cmdline.txt 
dwc_otg.lpm_enable=0 root=/dev/mmcblk0p2 rootfstype=ext4 rootflags=commit=120,data=writeback elevator=deadline rootwait quiet
Tuning sysctl.conf:
as manual say, sysctl.conf is the “Configuration file for setting system variables”... well there are lot of variables you can put inside this file and for everyone we can write a book.
Our goal is to gain more speed and tell our system to use less io/ram. Let’s put in the /etc/sysctl.conf:
vm.dirty_background_ratio = 20
vm.dirty_expire_centisecs = 0
vm.dirty_ratio = 80
vm.dirty_writeback_centisecs = 1200
vm.overcommit_ratio = 2
vm.laptop_mode = 5
vm.swappiness = 10
Removing unused services:
Removing services is a must to do for every system or computer, i have see some linux server with 256Mb of RAM with bluetooth, pcmcia etc etc service enabled... or pc with 100% cpu busy to run some 3d tube screensaver installed by default... also in Debian RaspberryPi official distro...
Automatically startx on boot:
I didn't use session/desktop manager like gdm, xdm or slim, it’s take ram and slow down starting up. Simply way is to use inittab:
vi /etc/inittab
1:2345:respawn:/bin/login -f root tty1
/dev/tty1 2>&1 (default is 1:23:respawn:/sbin/getty 38400 tty1)
and add this to .bash_profile on root home:
if [[ -z $DISPLAY ]] && [[ $(tty) = /dev/tty1 ]]; then
  exec startx >/dev/null 2>&1
fi