Setup Mikrotik OpenVPN Server using CAcert with Linux Client

Creating Mikrotik OpenVPN Server Certificates

OpenVPN works with SSL certificates. You can either use http://cacert.org to issue these or use the easy-rsa scripts, that come with most OpenVPN distributions. On RouterOS, all you have to do is to upload them via ftp (ca certificate and router certificate and private key) and import them with . . . → Read More: Setup Mikrotik OpenVPN Server using CAcert with Linux Client

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This tutorial will explain Export the DHCP database from a server that is running Microsoft Windows Server 2003 or Windows Server 2008 To move a DHCP database and configuration from a server that is running Windows Server 2003 or Windows Server 2008 to another server that is running Windows Server 2008.Read more: http://www.technohub.in/how-to-migrate-dhcp-server-from-a-windows-server-2003-to-windows-server-2008.html#ixzz0tBxuZGCC Under . . . → Read More: Step By Step Tutorial How to migrate DHCP server from a Windows server 2003 to Windows server 2008

IPv6 resources, documents, tutorials and guides

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Continue reading IPv6 resources, documents, tutorials and guides

802.11n Modulation and Coding Schemes (MCS)


MCS Index Modulation Rate Code NBPSCS(iSS) NSD NSP NCBPS NDBPS Rate Mb/s @ 20MHz Rate Mb/s@ 40MHz
(20MHz/40MHz) (20MHz/40MHz) (20MHz/40MHz) (20MHz/40MHz) 800ns GI 400ns GI 800ns GI 400ns GI

0 BPSK 1/2 1 52/108 4/6 52/108 26/54 6.5 7.2 13.5 15.0
1 QPSK 1/2 2 52/108 4/6 104/216 52/108 13.0 14.4 27.0 30.0
2 QPSK 3/4 2 52/108 4/6 104/216 78/162 19.5 21.7 40.5 45.0
3 16-QAM 1/2 4 52/108 4/6 208/432 104/216 26.0 28.9 54.0 60.0
4 16-QAM 3/4 4 52/108 4/6 208/432 156/324 39.0 43.3 81.0 90.0
5 64-QAM 2/3 6 52/108 4/6 312/648 208//432 52.0 57.8 108.0 120.0
6 64-QAM 3/4 6 52/108 4/6 312/648 234/486 58.5 65.0 121.5 135.0
7 64-QAM 5/6 6 52/108 4/6 312/648 260/540 65.0 72.2 135.0 150.0

8 BPSK 1/2 1 52/108 4/6 104/216 52/108 13.0 14.4 27.0 30.0
9 QPSK 1/2 2 52/108 4/6 208/432 104/216 26.0 28.9 54.0 60.0
10 QPSK 3/5 2 52/108 4/6 208/432 156/324 39.0 43.3 81.0 90.0
11 16-QAM 1/2 4 52/108 4/6 416/864 208/432 52.0 57.8 108.0 120.0
12 16-QAM 3/4 4 52/108 4/6 416/864 312/648 78.0 86.7 162.0 180.0
13 64-QAM 2/3 6 52/108 4/6 624/1296 416/864 104.0 115.6 216.0 240.0
14 64-QAM 3/4 6 52/108 4/6 624/1296 468/972 117.0 130.0 243.0 270.0
15 64-QAM 5/6 6 52/108 4/6 624/1296 520/1080 130.0 144.4 270.0 300.0

16 BPSK 1/2 1 52/108 4/6 156/324 78/162 19.5 21.7 40.5 45.0
17 QPSK 1/2 2 52/108 4/6 312/648 156/324 39.0 43.3 81.0 90.0
18 QPSK 3/5 2 52/108 4/6 312/648 234/486 58.5 65.0 121.5 135.0
19 16-QAM 1/2 4 52/108 4/6 624/1296 312/648 78.0 87.6 162.0 180.0
20 16-QAM 3/4 4 52/108 4/6 624/1296 468/972 117.0 130.0 243.0 270.0
21 64-QAM 2/3 6 52/108 4/6 936/1944 624/1296 156.0 173.3 324.0 360.0
22 64-QAM 3/4 6 52/108 4/6 936/1944 702/1458 175.5 195.0 364.5 405.0
23 64-QAM 5/6 6 52/108 4/6 936/1944 780/1620 195.0 216.7 405.0 450.0

24 BPSK 1/2 1 52/108 4/6 208/432 104/216 26.0 28.9 54.0 60.0
25 QPSK 1/2 2 52/108 4/6 416/864 208/432 52.0 57.8 108.0 120.0
26 QPSK 3/5 2 52/108 4/6 416/864 312/648 78.0 86.7 162.0 180.0
27 16-QAM 1/2 4 52/108 4/6 832/1728 416/864 104.0 115.6 216.0 240.0
28 16-QAM 3/4 4 52/108 4/6 832/1728 624/1296 156.0 173.3 324.0 360.0
29 64-QAM 2/3 6 52/108 4/6 1248/2592 832/1728 208.0 231.1 432.0 480.0
30 64-QAM 3/4 6 52/108 4/6 1248/2592 936/1944 234 260.0 486.0 540.0
31 64-QAM 5/6 6 52/108 4/6 1248/2592 1040/2160 260.0 288.9 540.0 600.0

32 BPSK 1/2 1 NA/48 NA/4 NA/48 NA/24 NA NA 6.0 6.7

NBPSCS(iSS) = Number of coded bits per single carrier

NSD = Number of data sub-carriers

NSP = Number of pilot sub-carriers (used for pilot tracking)

NCBPS = Number of coded bits per OFDM symbol

NDBPS = Number of data bits per OFDM symbol

MCS 0 – 7 are for 1×1 MIMO (1 spacial stream), MCS 8 – 15 are 2×2 MIMO (2 spacial streams). MCS 16 – 23 are 3×3 MIMO (3 spacial streams) and MCS 24 – 31 are for 4×4 MIMO (4 spacial streams).

Ο vendor are obliged to support MCS 0 – 15  depending on weather they implement 1×1 or 2×2 MIMO at 20MHz.  Support for 40MHz and the rest of MCS is optional.

MCS 32 is special for high noise environments and it basically does duplication of data, its BPSK with 1 spacial stream in 40MHz only and with max rate  6.7Mb/s .

MCS 33 – 76 are in unequal modulation of 2 spacial streams upwards, in other words every stream has different modulation (QPSK/QAM), the 33 – 38 has 2 streams (max 108.3Mb/s @ 20MHz, 225Mb/s @ 40MHz), 39 – 52 has 3 streams (max 173,3Mb/s @20MHz, 360Mb/s @ 40MHz) and  53 – 76 has 4 streams (max 238Mb/s @ 20MHz, 495Μb/s @ 40MHz). The purpose is to have flexibility and better adaptivity to environment conditions (all this provided there is in place an advanced rate control algorithm that takes into account many different parameters).

MCS 77 – 127 are reserved.

Continue reading 802.11n Modulation and Coding Schemes (MCS)