Ohun gbogbo ti o fẹ lati mọ nipa awọn Mac adirẹsi

Gbogbo eniyan mọ pe awọn baiti mẹfa wọnyi, ti o han nigbagbogbo ni ọna kika hexadecimal, ni a yàn si kaadi nẹtiwọki ni ile-iṣẹ, ati pe o dabi ẹnipe laileto. Diẹ ninu awọn eniyan mọ pe awọn baiti mẹta akọkọ ti adirẹsi naa jẹ ID olupese, ati pe awọn baiti mẹta ti o ku ni a yan fun wọn. O tun mọ pe o le ṣeto ara rẹ lainidii adirẹsi. Ọpọlọpọ eniyan ti gbọ nipa “awọn adirẹsi laileto” ni Wi-Fi.

Jẹ ká ro ero ohun ti o jẹ.

Adirẹsi MAC (adirẹsi iṣakoso iwọle media) jẹ idanimọ alailẹgbẹ ti a sọtọ si ohun ti nmu badọgba nẹtiwọọki kan, ti a lo ninu awọn nẹtiwọọki ti awọn ajohunše IEEE 802, paapaa Ethernet, Wi-Fi ati Bluetooth. Ni ifowosi o ni a npe ni "EUI-48 iru idamo". Lati orukọ naa o han gbangba pe adirẹsi naa jẹ 48 bit gigun, i.e. 6 baiti. Ko si boṣewa ti a gba ni gbogbogbo fun kikọ adirẹsi kan (ni idakeji si adiresi IPv4, nibiti awọn octets ti wa niya nigbagbogbo nipasẹ awọn aami). 00, biotilejepe diẹ ninu awọn olupese ẹrọ fẹ akiyesi 11 -AB-CD-EF-22-00 ati paapa 11ab.cdef.22.

Láti ìgbà kan rí, a ti ṣètò àwọn àdírẹ́sì sínú chipset ROM ti káàdì nẹ́tíwọ́ọ̀kì náà, a kò sì le ṣe àtúnṣe rẹ̀ láìsí flash programmer, ṣùgbọ́n ní òde òní, a le yí àdírẹ́sì náà padà nípasẹ̀ ètò láti inú ẹ̀rọ ìṣiṣẹ́. O le fi ọwọ́ ṣe àdírẹ́sì MAC ti káàdì nẹ́tíwọ́ọ̀kì náà. Linux àti MacOS (nígbà gbogbo), Windows (ó fẹ́rẹ̀ẹ́ jẹ́ pé nígbà gbogbo, tí awakọ̀ bá gbà láyè), Android (gbòǹgbò nìkan); pẹ̀lú iOS (láìsí gbòǹgbò) irú ọgbọ́n bẹ́ẹ̀ kò ṣeé ṣe.

Ilana adirẹsi

Adirẹsi naa ni apakan ti idamọ olupese, OUI, ati idamọ ti a yàn nipasẹ olupese. Iṣẹ iyansilẹ ti OUI (Idamo Alailẹgbẹ Ti Apejọ) awọn idanimọ npe ni IEEE agbari. Ni pato, awọn oniwe-ipari le jẹ ko nikan 3 baiti (24 die-die), ṣugbọn 28 tabi 36 die-die, lati eyi ti ohun amorindun (MAC Adirẹsi Block, MA) ti awọn adirẹsi ti awọn iru Tobi (MA-L), Alabọde (MA-M) ati Kekere ti wa ni akoso (MA-S) lẹsẹsẹ. Iwọn ti bulọọki ti a ti pese, ninu ọran yii, yoo jẹ 24, 20, 12 bits tabi 16 million, 1 million, 4 ẹgbẹrun adirẹsi. Lọwọlọwọ o wa nipa awọn bulọọki 38 ẹgbẹrun ti o pin, wọn le wo ni lilo ọpọlọpọ awọn irinṣẹ ori ayelujara, fun apẹẹrẹ IEEE tabi Wireshark.

Tani o ni awọn adirẹsi?

Irọrun processing ti gbangba wa unloading infomesonu IEEE n pese alaye pupọ pupọ. Fun apẹẹrẹ, diẹ ninu awọn ajo ti mu ọpọlọpọ awọn bulọọki OUI fun ara wọn. Eyi ni awọn akọni wa:

Olutaja
Nọmba awọn bulọọki / awọn igbasilẹ
Nọmba awọn adirẹsi, milionu

Cisco Systems Inc
888
14208

Apple
772
12352

Samsung
636
10144

Huawei Technologies Co.Ltd
606
9696

Intel Corporation
375
5776

ARRIS Group Inc.
319
5104

Ile-iṣẹ Nokia
241
3856

ikọkọ
232
2704

Texas Instruments
212
3392

ile-iṣẹ zte
198
3168

IEEE Iforukọsilẹ Authority
194
3072

Hewlett Packard
149
2384

Hon Hai konge
136
2176

TP-RÁNṢẸ
134
2144

Dell Inc.
123
1968

Awọn ile-iṣẹ Juniper
110
1760

Sagemcom Broadband SAS
97
1552

Fiberhome Telecommunication Technologies Co. LTD
97
1552

Xiaomi Communications Co., Ltd
88
1408

Guangdong Oppo Mobile Telecommunications Corp.Ltd
82
1312

Google ni 40 nikan ninu wọn, ati pe eyi kii ṣe iyalẹnu: awọn tikararẹ ko ṣe ọpọlọpọ awọn ẹrọ nẹtiwọọki.

MA ohun amorindun ko ba wa ni pese free , ti won le wa ni ra fun a reasonable owo (lai a alabapin owo) $ 3000, $ 1800 tabi $ 755, lẹsẹsẹ. O yanilenu, fun afikun owo (fun ọdun kan) o le ra “fipamọ” ti alaye ti gbogbo eniyan nipa bulọọki ti a pin. O ti wa ni bayi 232 ti wọn, bi a ti le ri loke.

Nigbawo ni a yoo pari awọn adirẹsi MAC?

Gbogbo wa ni o rẹ wa lẹwa ti awọn itan ti o ti n lọ fun ọdun 10 ti “awọn adirẹsi IPv4 ti fẹrẹ pari.” Bẹẹni, awọn bulọọki IPv4 tuntun ko rọrun lati gba. O mọ pe awọn adirẹsi IP lalailopinpin unevenly pin; Awọn bulọọki gigantic ati awọn bulọọki ti ko lo ohun ini nipasẹ awọn ile-iṣẹ nla ati awọn ile-iṣẹ ijọba AMẸRIKA, sibẹsibẹ, pẹlu ireti diẹ ti pinpin wọn si awọn ti o nilo. Ilọsiwaju ti NAT, CG-NAT ati IPv6 ti jẹ ki iṣoro ti aito awọn adirẹsi gbogbo eniyan kere si.

Adirẹsi MAC kan ni awọn iwọn 48, eyiti 46 le jẹ “wulo” (kilode? ka lori), eyiti o fun awọn adirẹsi 246 tabi 1014, eyiti o jẹ awọn akoko 214 diẹ sii ju aaye adirẹsi IPv4 lọ.
Lọwọlọwọ, o fẹrẹ to idaji aimọye awọn adirẹsi ti pin, tabi nikan 0.73% ti iwọn didun lapapọ. A tun wa pupọ, jinna pupọ lati ṣiṣe awọn adirẹsi MAC.

Aileto die-die

A le ro pe awọn OUI ti pin laileto, ati pe olutaja lẹhinna tun fi awọn adirẹsi sọtọ laileto si awọn ẹrọ nẹtiwọọki kọọkan. Ṣe eyi jẹ otitọ? Jẹ ki a wo pinpin awọn die-die ni awọn apoti isura data ti awọn adirẹsi MAC ti awọn ẹrọ 802.11 ti o wa ni isunmọ mi, ti a gba nipasẹ awọn ọna ṣiṣe aṣẹ iṣẹ ni awọn nẹtiwọọki alailowaya WNAM. Awọn adirẹsi jẹ ti awọn ẹrọ gidi ti o sopọ si Wi-Fi fun ọpọlọpọ ọdun ni awọn orilẹ-ede mẹta. Ni afikun nibẹ ni a kekere database ti 802.3 ti firanṣẹ LAN awọn ẹrọ.

Jẹ ki a ya lulẹ adirẹsi MAC kọọkan (awọn baiti mẹfa) ti ọkọọkan awọn ayẹwo sinu awọn die-die, baiti nipasẹ baiti, ati wo igbohunsafẹfẹ ti iṣẹlẹ ti “1” bit ni ọkọọkan awọn ipo 48. Ti o ba ṣeto bit naa ni ọna lainidii patapata, lẹhinna iṣeeṣe ti gbigba “1” yẹ ki o jẹ 50%.

Wi-Fi yiyan No.. 1 (RF)
Apeere Wi-Fi No. 2 (Belarus)
Wi-Fi yiyan No.. 3 (Uzbekisitani)
Iṣapẹẹrẹ LAN (RF)

Nọmba awọn igbasilẹ ninu ibi ipamọ data
5929000
1274000
366000
1000

Nọmba Bit:
% bit "1"
% bit "1"
% bit "1"
% bit "1"

1
48.6%
49.2%
50.7%
28.7%

2
44.8%
49.1%
47.7%
30.7%

3
46.7%
48.3%
46.8%
35.8%

4
48.0%
48.6%
49.8%
37.1%

5
45.7%
46.9%
47.0%
32.3%

6
46.6%
46.7%
47.8%
27.1%

7
0.3%
0.3%
0.2%
0.7%

8
0.0%
0.0%
0.0%
0.0%

9
48.1%
50.6%
49.4%
38.1%

10
49.1%
50.2%
47.4%
42.7%

11
50.8%
50.0%
50.6%
42.9%

12
49.0%
48.4%
48.2%
53.7%

13
47.6%
47.0%
46.3%
48.5%

14
47.5%
47.4%
51.7%
46.8%

15
48.3%
47.5%
48.7%
46.1%

16
50.6%
50.4%
51.2%
45.3%

17
49.4%
50.4%
54.3%
38.2%

18
49.8%
50.5%
51.5%
51.9%

19
51.6%
53.3%
53.9%
42.6%

20
46.6%
46.1%
45.5%
48.4%

21
51.7%
52.9%
47.7%
48.9%

22
49.2%
49.6%
41.6%
49.8%

23
51.2%
50.9%
47.0%
41.9%

24
49.5%
50.2%
50.1%
47.5%

25
47.1%
47.3%
47.7%
44.2%

26
48.6%
48.6%
49.2%
43.9%

27
49.8%
49.0%
49.7%
48.9%

28
49.3%
49.3%
49.7%
55.1%

29
49.5%
49.4%
49.8%
49.8%

30
49.8%
49.8%
49.7%
52.1%

31
49.5%
49.7%
49.6%
46.6%

32
49.4%
49.7%
49.5%
47.5%

33
49.4%
49.8%
49.7%
48.3%

34
49.7%
50.0%
49.6%
44.9%

35
49.9%
50.0%
50.0%
50.6%

36
49.9%
49.9%
49.8%
49.1%

37
49.8%
50.0%
49.9%
51.4%

38
50.0%
50.0%
49.8%
51.8%

39
49.9%
50.0%
49.9%
55.7%

40
50.0%
50.0%
50.0%
49.5%

41
49.9%
50.0%
49.9%
52.2%

42
50.0%
50.0%
50.0%
53.9%

43
50.1%
50.0%
50.3%
56.1%

44
50.1%
50.0%
50.1%
45.8%

45
50.0%
50.0%
50.1%
50.1%

46
50.0%
50.0%
50.1%
49.5%

47
49.2%
49.4%
49.7%
45.2%

48
49.9%
50.1%
50.7%
54.6%

Kilode ti iru aiṣedede bẹ ni 7 ati 8 bits? Nibẹ ni o wa fere nigbagbogbo odo.

Lootọ, boṣewa n ṣalaye awọn iwọn wọnyi bi pataki (Wikipedia):

Ẹkẹjọ (lati ibẹrẹ) bit ti baiti akọkọ ti adirẹsi MAC ni a pe ni Unicast/Multicast bit ati pinnu iru fireemu (fireemu) ti a gbejade pẹlu adirẹsi yii, deede (0) tabi igbohunsafefe (1) (multicast tabi igbohunsafefe). Fun deede, ibaraẹnisọrọ oluyipada nẹtiwọọki unicast, bit yii ti ṣeto si “0” ni gbogbo awọn apo-iwe ti a firanṣẹ si.

Keje (lati ibẹrẹ) bit ti akọkọ baiti ti adirẹsi MAC ni a npe ni U/L (Universal/Local) bit ati pinnu boya adirẹsi naa jẹ alailẹgbẹ agbaye (0), tabi alailẹgbẹ agbegbe (1). Nipa aiyipada, gbogbo awọn adirẹsi “olupese-stitched” jẹ alailẹgbẹ agbaye, nitorinaa opo julọ ti awọn adirẹsi MAC ti a gbajọ ni ipin keje ti a ṣeto si “0”. Ninu tabili ti awọn idamọ OUI ti a ti sọtọ, awọn titẹ sii 130 nikan ni U/L bit ti “1”, ati pe o han gbangba pe iwọnyi jẹ awọn bulọọki ti awọn adirẹsi MAC fun awọn iwulo pataki.

Lati kẹfa si awọn die-die akọkọ ti baiti akọkọ, awọn bit ti awọn baiti keji ati kẹta ni awọn idamọ OUI, ati paapaa diẹ sii awọn bit ti o wa ninu awọn baiti 4-6 ti adirẹsi ti olupese ti pin si diẹ sii tabi kere si ni deede. .

Nitorinaa, ninu adiresi MAC gidi ti oluyipada nẹtiwọọki, awọn bit jẹ deede deede ati pe ko ni itumọ imọ-ẹrọ, pẹlu ayafi awọn die-die iṣẹ meji ti baiti giga.

Itankale

Iyalẹnu kini awọn olupese ẹrọ alailowaya jẹ olokiki julọ? Jẹ ki a ṣajọpọ wiwa ni aaye data OUI pẹlu data lati apẹẹrẹ No.. 1.

Olutaja
Pipin awọn ẹrọ, %

Apple
26,09

Samsung
19,79

Huawei Technologies Co. Ltd
7,80

Xiaomi Communications Co., Ltd
6,83

Sony Mobile Communications Inc
3,29

LG Electronics (Awọn ibaraẹnisọrọ Alagbeka)
2,76

ASUSTek KỌMPUTA INC.
2,58

TCT mobile Ltd
2,13

ile-iṣẹ zte
2,00

ko ri ni IEEE database
1,92

Lenovo Mobile Communication Technology Ltd.
1,71

Ile-iṣẹ Eshitisii
1,68

Murata iṣelọpọ
1,31

InPro Comm
1,26

Microsoft Corporation
1,11

Shenzhen TINNO Mobile Technology Corp.
1,02

Motorola (Wuhan) Ibaraẹnisọrọ Ibaraẹnisọrọ Co. Ltd.
0,93

Ile-iṣẹ Nokia
0,88

Awọn iṣiro ti ile-iṣẹ Shanghai Wind Technologies Co., Ltd. Ltd
0,74

Lenovo Mobile Communication (Wuhan) Company Limited
0,71

Iṣeṣe fihan pe diẹ sii ni ilọsiwaju ti awọn alabapin ti awọn alabapin nẹtiwọki alailowaya ni ipo ti a fun, ti o pọju ipin ti awọn ẹrọ Apple.

Aṣoṣo

Ṣe awọn adirẹsi MAC jẹ alailẹgbẹ bi? Ni imọran, bẹẹni, niwọn igba ti olupese ẹrọ kọọkan (Oluwa block MA) nilo lati pese adirẹsi alailẹgbẹ kan fun ọkọọkan awọn oluyipada nẹtiwọọki ti o ṣe. Sibẹsibẹ, diẹ ninu awọn aṣelọpọ chirún, eyun:

• 00:0A:F5 Airgo Networks, Inc. (bayi Qualcomm)
• 00:08:22 InPro Comm (bayi MediaTek)

ṣeto awọn baiti mẹta ti o kẹhin ti adiresi MAC si nọmba ID, nkqwe lẹhin atunbere ẹrọ kọọkan. Iru awọn adirẹsi bẹẹ 1 ẹgbẹrun wa ninu apẹẹrẹ No.. 82 mi.

O le, nitootọ, ṣeto ararẹ ni ajeji, adirẹsi ti kii ṣe alailẹgbẹ nipa siseto ni ipinnu “gẹgẹbi ti aladugbo rẹ”, ṣe idanimọ rẹ pẹlu apanirun, tabi yiyan ni laileto. O tun ṣee ṣe lati ṣeto ararẹ lairotẹlẹ adirẹsi ti kii ṣe alailẹgbẹ nipasẹ, fun apẹẹrẹ, mimu-pada sipo iṣeto afẹyinti ti olulana bi Mikrotik tabi OpenWrt.

Kini yoo ṣẹlẹ ti awọn ẹrọ meji ba wa lori nẹtiwọọki pẹlu adirẹsi MAC kanna? Gbogbo rẹ da lori imọran ti ohun elo nẹtiwọọki (olulana ti a firanṣẹ, oludari nẹtiwọọki alailowaya). O ṣeese julọ, awọn ẹrọ mejeeji yoo boya ko ṣiṣẹ tabi yoo ṣiṣẹ lainidii. Lati oju-ọna ti awọn iṣedede IEEE, aabo lodi si adiresi MAC ti o ti sọ di mimọ ni a dabaa lati yanju ni lilo, fun apẹẹrẹ, MACsec tabi 802.1X.

Kini ti o ba fi MAC sori ẹrọ pẹlu ipin keje tabi kẹjọ ti ṣeto si “1”, i.e. agbegbe tabi multicast adirẹsi? O ṣeese julọ, nẹtiwọọki rẹ kii yoo san ifojusi si eyi, ṣugbọn ni deede iru adirẹsi kan kii yoo ni ibamu pẹlu boṣewa, ati pe o dara lati ma ṣe bẹ.

Bawo ni randomization ṣiṣẹ

A mọ pe lati le ṣe idiwọ ipasẹ awọn agbeka eniyan nipasẹ ṣiṣe ọlọjẹ ati gbigba awọn igbi afẹfẹ, awọn ọna ṣiṣe ẹrọ foonuiyara MAC ti nlo imọ-ẹrọ aileto fun ọpọlọpọ ọdun. Ni imọ-jinlẹ, nigbati o ba n ṣayẹwo awọn igbi afẹfẹ ni wiwa awọn nẹtiwọọki ti a mọ, foonuiyara firanṣẹ apo-iwe kan (ẹgbẹ ti awọn apo-iwe) ti iru ibeere ibeere 802.11 pẹlu adirẹsi MAC bi orisun:

Aileto ti a mu ṣiṣẹ gba ọ laaye lati pato kii ṣe “stitched” ọkan, ṣugbọn diẹ ninu awọn adirẹsi orisun soso miiran, iyipada pẹlu yiyika wiwa kọọkan, ni akoko pupọ, tabi ni ọna miiran. Ṣe o ṣiṣẹ? Jẹ ki a wo awọn iṣiro ti awọn adirẹsi MAC ti a gba lati afẹfẹ nipasẹ ohun ti a pe ni “Wi-Fi Radar”:

Gbogbo apẹẹrẹ
Ayẹwo nikan pẹlu odo 7th bit

Nọmba awọn igbasilẹ ninu ibi ipamọ data
3920000
305000

Nọmba Bit:
% bit "1"
% bit "1"

1
66.1%
43.3%

2
66.5%
43.4%

3
31.7%
43.8%

4
66.6%
46.4%

5
66.7%
45.7%

6
31.9%
46.4%

7
92.2%
0.0%

8
0.0%
0.0%

9
67.2%
47.5%

10
32.3%
45.6%

11
66.9%
45.3%

12
32.3%
46.8%

13
32.6%
50.1%

14
33.0%
56.1%

15
32.5%
45.0%

16
67.2%
48.3%

17
33.2%
56.9%

18
33.3%
56.8%

19
33.3%
56.3%

20
66.8%
43.2%

21
67.0%
46.4%

22
32.6%
50.1%

23
32.9%
51.2%

24
67.6%
52.2%

25
49.8%
47.8%

26
50.0%
50.0%

27
50.0%
50.2%

28
50.0%
49.8%

29
50.0%
49.4%

30
50.0%
50.0%

31
50.0%
49.7%

32
50.0%
49.9%

33
50.0%
49.7%

34
50.0%
49.6%

35
50.0%
50.1%

36
50.0%
49.5%

37
50.0%
49.9%

38
50.0%
49.8%

39
50.0%
49.9%

40
50.0%
50.1%

41
50.0%
50.2%

42
50.0%
50.2%

43
50.0%
50.1%

44
50.0%
50.1%

45
50.0%
50.0%

46
50.0%
49.8%

47
50.0%
49.8%

48
50.1%
50.9%

Aworan naa yatọ patapata.

Iwọn 8th ti baiti akọkọ ti adiresi MAC tun ni ibamu si ẹda Unicast ti adiresi SRC ninu apo ibeere ibeere.

Awọn 7th bit ti ṣeto si Agbegbe ni 92.2% awọn iṣẹlẹ, i.e. Pẹlu a itẹ ìyí ti igbekele, a le ro pe gangan ki ọpọlọpọ awọn ti awọn ti gba adirẹsi ti wa ni aileto, ati ki o kere ju 8% jẹ gidi. Ni idi eyi, pinpin awọn ege ni OUI fun iru awọn adirẹsi gidi ni isunmọ ni ibamu pẹlu data ninu tabili iṣaaju.

Olupese wo, ni ibamu si OUI, ni awọn adirẹsi aileto (ie pẹlu 7th bit ni “1”)?

Olupese nipa OUI
Pin laarin gbogbo awọn adirẹsi

ko ri ni IEEE database
62.45%

Google Inc.
37.54%

isinmi
0.01%

Pẹlupẹlu, gbogbo awọn adirẹsi ti a sọtọ si Google jẹ ti OUI kanna pẹlu ìpele DA:A1:19. Kí ni ìpilẹ̀ṣẹ̀ yìí? Jẹ ki a wo inu awọn orisun Android.

private static final MacAddress BASE_GOOGLE_MAC = MacAddress.fromString("da:a1:19:0:0:0");

Iṣura Android nlo pataki kan, OUI ti a forukọsilẹ nigbati o n wa awọn nẹtiwọọki alailowaya, ọkan ninu awọn diẹ ti o ni ipilẹ bit keje.

Ṣe iṣiro MAC gidi lati ọkan laileto

Jẹ ki a wo nibẹ:

private static final long VALID_LONG_MASK = (1L << 48) - 1;
private static final long LOCALLY_ASSIGNED_MASK = MacAddress.fromString("2:0:0:0:0:0").mAddr;
private static final long MULTICAST_MASK = MacAddress.fromString("1:0:0:0:0:0").mAddr;

public static @NonNull MacAddress createRandomUnicastAddress(MacAddress base, Random r) {
        long addr;
        if (base == null) {
            addr = r.nextLong() & VALID_LONG_MASK;
        } else {
            addr = (base.mAddr & OUI_MASK) | (NIC_MASK & r.nextLong());
        }
        addr |= LOCALLY_ASSIGNED_MASK;
        addr &= ~MULTICAST_MASK;
        MacAddress mac = new MacAddress(addr);
        if (mac.equals(DEFAULT_MAC_ADDRESS)) {
            return createRandomUnicastAddress(base, r);
        }
        return mac;
    }

Gbogbo adiresi naa, tabi awọn baiti mẹta ti isalẹ rẹ, jẹ mimọ Random.extLong()“Àtúnṣe ìwé àṣẹ-àṣẹ ti MAC gidi” jẹ́ ẹ̀tàn. A lè retí pẹ̀lú ìdánilójú gíga pé àwọn olùṣelọpọ yóò ṣe bẹ́ẹ̀. AndroidÀwọn OUI mìíràn tí kò forúkọ sílẹ̀ ni a tún ń lò nínú àwọn fóònù. A kò ní koodu orísun iOS, ṣùgbọ́n ó ṣeé ṣe kí a lo algoridimu kan náà níbẹ̀.

Eyi ti o wa loke ko fagile iṣẹ ti awọn ọna ṣiṣe miiran fun de-anonymizing awọn alabapin Wi-Fi, da lori itupalẹ awọn aaye miiran ti fireemu ibeere ibeere, tabi ibamu ti igbohunsafẹfẹ ibatan ti awọn ibeere ti ẹrọ naa firanṣẹ. Bibẹẹkọ, titọpa igbẹkẹle alabapin kan nipa lilo awọn ọna ita jẹ iṣoro pupọju. Awọn data ti a gba yoo jẹ diẹ dara fun itupalẹ apapọ / fifuye giga nipasẹ ipo ati akoko, da lori awọn nọmba nla, laisi itọkasi awọn ẹrọ kan pato ati eniyan. Awọn “inu” nikan, awọn oluṣelọpọ OS alagbeka funrararẹ, ati awọn ohun elo ti a fi sii ni data deede.

Kí ló léwu tó bá ṣẹlẹ̀ pé ẹnìkan ń kọ́ àdírẹ́sì MAC ti ẹ̀rọ rẹ? A lè ṣe ìkọlù ìkọ̀sílẹ̀ iṣẹ́ lórí àwọn nẹ́tíwọ́ọ̀kì onírin àti àwọn nẹ́tíwọ́ọ̀kì aláìlọ́wọ́. Fún ẹ̀rọ aláìlọ́wọ́, ó ṣeé ṣe kí a rí wíwà rẹ̀ ní ibi tí sensọ̀ náà wà. A lè lo ìfọ́mọ́ àdírẹ́sì láti ṣe bí ẹ̀rọ rẹ, ṣùgbọ́n èyí yóò ṣiṣẹ́ kìkì tí àwọn ìgbésẹ̀ ààbò afikún (àṣẹ àti/tàbí ìfọwọ́sowọ́pọ̀) kò bá sí. 99.9% Àwọn ènìyàn níbí kò ní ohunkóhun láti ṣàníyàn nípa rẹ̀.

Adirẹsi MAC jẹ idiju diẹ sii ju bi o ti dabi, ṣugbọn rọrun ju bi o ti le jẹ.

orisun: www.habr.com