reverse phone lookup



reverse lookup

reverse lookup

Reverse DNS lookup is a process to determine the hostname associated with a given IP address.

Typically, the DNS is used to determine what IP address is associated with a given hostname; so to reverse resolve a known IP address is to lookup what the associated hostname for it is. A reverse lookup is often referred to simply as reverse resolving, or more specifically reverse DNS lookups.

Contents

  • 1 IPv4 Reverse DNS
    • 1.1 Classless Reverse DNS
  • 2 IPv6 Reverse Lookup
  • 3 Uses
  • 4 External links

IPv4 Reverse DNS

Reverse DNS lookups for IPv4 addresses use the special domain in-addr.arpa. An IPv4 address is represented in the in-addr.arpa domain by a sequence of bytes in reverse order, represented as decimal numbers, separated by dots with the suffix .in-addr.arpa. For example, the reverse lookup domain name corresponding to the IPv4 address 101.102.103.104 is 104.103.102.101.in-addr.arpa. A host name for 1.2.3.4 can be obtained by issuing a DNS query for the PTR record for that special address 4.3.2.1.in-addr.arpa.

Classless Reverse DNS

Historically, IP addresses were allocated in blocks of 256. Thus, each block fell upon a octet boundary. This made configuration of the PTR records easy, since the dot separators delimited each block. Today however, IP addresses are allocated in very much smaller blocks, and hence the tradtional way of configuring a nameserver to perform reverse DNS cannot work. A means of overcoming this problem was devised and published as RFC 2317. It uses a CNAME entry which corresponds to each block.

IPv6 Reverse Lookup

Reverse DNS lookups for IPv6 addresses use similarly the special domain ip6.arpa. An IPv6 address is represented as a name in the ip6.arpa domain by a sequence of nibbles in reverse order, represented as hexadecimal digits, separated by dots with the suffix .ip6.arpa. For example, the reverse lookup domain name corresponding to the IPv6 address 4321:0:1:2:3:4:567:89ab is b.a.9.8.7.6.5.0.4.0.0.0.3.0.0.0.2.0.0.0.1.0.0.0.0.0.0.0.1.2.3.4.ip6.arpa.

Uses

Reverse DNS was designed to be primarily a tool for network troubleshooting. However, it is sometimes used as a poor defence against spam. When an Internet mail server receives incoming mail from an external machine, it may check that the reverse DNS record for the IP address of the originating server matches up with name by which the originating server identifies itself during the SMTP greeting.

For example:

  • Mail Server A receives an incoming SMTP connection from machine B (it appears to A, that the connection from B originates from IP address X).
  • As part of the SMTP transaction, machine B identifies itself to Server A by saying: "HELO mailserver.example.domain".
  • Mail Server A then carries out a reverse DNS lookup on IP address X - if the reverse (PTR record) matches the name "mailserver.example.domain", then mail server A has a greater degree of certainty that the incoming mail is legitimate because, for machines which send out spam, this often isn't the case.

This is not a good defence against spam for several reasons. One is that a machine can have more than one IP address and any number of domain names, and the mapping between IP addresses and domain names is essentially arbitrary. Another, perhaps more relevant, reason is that a single client or server machine can legitimately send mail that is "from" an address in a domain different from that of the machine. There is no expected relationship between the domain name of a mail client or server and the domain names of the email addresses whose mail it originates or accepts. This is intentional, and essential to allow the outsourcing of a company's email handling. A third reason is that due to NATs the source IP address seen by the server may be different than the source IP address used by the client. However, notwithstanding the above, many mail servers do perform this check, so most mail clients take pains to ensure that the domain name that appears in HELO or EHLO commands matches the one resulting from a reverse DNS lookup of the source IP address.

External links

  • How Reverse DNS Works
  • Reverse DNS Lookup Tool
Search Term: "Reverse_DNS_lookup"
reverse lookup news and reverse lookup articles

Here's our top rated reverse lookup links for the day:

Reverse Lookup 

About.com - Oct 03 10:30 PM
If you're trying to find someone's address or phone number, sometimes the easiest way to go about it is to use a reverse phonebook lookup. Usually, all you have...

Reverse Lookup Site Cellulartrace.com Has New Look; New Owner 
[Press Release] PR Web - Oct 04 12:28 AM
Leading investigative website Cellular-trace.com has changed, its look and its owner. The reverse lookup site's new management promises faster service, lower prices and more. (PRWEB Oct 4, 2006)

Yahoo, Verizon Lead Local Directory Searches 
WebProNews - Oct 11 2:41 PM
A recent comScore analysis revealed that not only are significantly greater numbers of Internet users turning to the Web to find local information, but two sites, Yahoo and Verizon, dominate the scene. The first of a two-part series of studies, comScore found that 68 million US Internet users searched for business directory listings on the Local sections of major search sites (e.g. Yahoo! Local

Thank you for viewing the reverse lookup page reverse lookup. 

reverse lookup
revers look up
reverse lok up
revrse look up
reverse loo up
revese look up
reverse lool up
reverse look p
reeverse look up
reverselookup
revers lookup
rverse lookup
reverse lokup
revrse lookup
revese lookup
reversr lookup
reverse lookuo
reverse ookup
reverse looku
reverse loolup
rreverse lookup
recerse lookup
reverse lookupp
reverse looup
reverse lookp
revere lookup
reverse lookip
reverse lookkup

 

 Ever wondered what others are searching for in relation to reverse lookup? Now you can see.  Below is a listing of  what everyone else is searching for in regard to reverse lookup.

1. reverse lookup
2. reverse phone lookup
3. reverse phone number lookup
4. reverse address lookup
5. reverse number lookup
6. free reverse lookup
7. free reverse phone number lookup
8. free reverse phone lookup
9. reverse telephone lookup
10. free reverse cell phone lookup
11. reverse cell phone lookup
12. reverse email lookup
13. cell phone reverse lookup
14. free reverse address lookup
15. free cell phone number reverse lookup
16. free reverse number lookup
17. phone number reverse lookup
18. reverse telephone number lookup
19. reverse lookup free
20. telephone reverse lookup
21. cellular reverse lookup
22. free cell phone reverse lookup
23. cell phone number reverse lookup
24. free reverse telephone number lookup
25. reverse phone lookup free
26. phone reverse lookup
27. free reverse telephone lookup
28. cell phone reverse lookup free
29. free reverse cell phone number lookup
30. reverse lookup phone number
31. canada reverse lookup
32. free reverse email lookup
33. reverse lookup phone numbers
34. email free reverse lookup
35. white pages reverse lookup
36. reverse lookup phone
37. reverse cell phone number lookup
38. reverse dns lookup
39. free unlisted reverse phone number lookup
40. reverse lookup cell phones
41. reverse phone number lookup free
42. free reverse cellular phone lookup
43. reverse cell phone number lookup free
44. reverse lookup address
45. reverse lookups
46. reverse phone lookups
47. reverse ip lookup
48. free reverse phone number lookup for canada
49. reverse area code lookup
50. cell phone reverse phone number lookup
51. free reverse lookup cell phone
52. reverse cell phone lookup free
53. area code reverse lookup
54. sprint free reverse cell phone number lookup
55. verizon reverse lookup
56. free reverse lookup cellular phones
57. telephone number reverse lookup
58. dogpile reverse lookup
59. free reverse cell lookup
60. cell free lookup number phone reverse
61. reverse business address lookup
62. reverse lookup by address
63. email directory reverse lookup
64. free reverse lookups
65. reverse cell lookup
66. email reverse lookup
67. free cellphone reverse lookup
68. hotmail email reverse lookup
69. free cell phone reverse number lookup
70. reverse number lookup on a cell phone
71. sprint reverse cell phone lookup free
72. cellular reverse lookup free
73. reverse fax number lookup
74. reverse lookup cell phone
75. reverse fax lookup
76. cell number phone reverse reverse phone lookup
77. free cell reverse lookup
78. reverse e-mail lookup
79. sprint reverse cell phone lookup
80. free sprint pcs cell phone reverse lookup
81. address reverse lookup
82. cell phone reverse number lookup
83. reverse lookup canada
84. reverse lookup cell phone number
85. reverse phone  lookup
86. reverse yahoo email lookup
87. cell lookup number phone reverse sprint
88. free reverse lookup service
89. cell phone number reverse lookup free
90. reverse cell number lookup
91. unlisted numbers free reverse lookup cell phone
92. cell lookup number phone reverse
93. cell lookup phone reverse sprint
94. lookup reverse cell phone number look up
95. sprint cell phone reverse lookup
96. email reverse lookup search
97. free cellular reverse lookup
98. lookup reverse cell phone number look
99. free reverse cell phone lookups
100. reverse lookup dogpile
101. yellow pages reverse lookup
102. free reverse cellphone lookup
103. free reverse phone lookups
104. free sprint cell phone reverse lookup
105. numbers lookup free reverse cell phone number look up
106. cell free lookup number phone phone reverse
107. cell free lookup phone reverse
108. free reverse license plate lookup
109. reverse lookup directory
110. reverse lookup telephone
111. alltel reverse cell phone lookup
112. free reverse lookup of cell phone numbers
113. sprint cell phone number reverse lookup
114. best totally free reverse cell phone number lookup
115. cellular mobile phone number reverse lookup
116. free fax reverse lookup
117. free reverse cell lookup mobile phone number look up
118. free reverse lookup cell phone number
119. numbers lookup free reverse cell phone number look
120. trace unlisted numbers free reverse lookup cell phone
121. canada reverse lookup cellular
122. cell free lookup phone reverse sprint
123. cell phone number 2146830630 reverse lookup free
124. cellphone reverse lookup
125. toll free reverse lookup
126. free reverse aol email lookup
127. free reverse lookup by cell cellular phone number
128. free reverse lookup phone numbers
129. reverse cellphone lookup
130. toll free number reverse lookup
131. anyone email find lookup reverse
132. cell free lookup numbers phone reverse
133. free phone number reverse lookup
134. freeality reverse lookup
135. reverse directory lookup
136. reverse phone number lookup cell phone free
137. find people reverse cell phone number lookup
138. free cell phone numbers reverse lookup
139. reverse telephone lookup free
140. cell phone number and reverse lookup
141. free cell phone number search reverse lookup
142. free reverse cell phone number lookups
143. reverse cell phone lookup free verizon
144. reverse nextel cell phone lookup free
145. cell phone number lookup reverse
146. cingular cell phone free reverse number lookup
147. free phone reverse lookup
148. free reverse lookup cell phone numbers
149. reverse zip code lookup
150. 4402417064free cell phone reverse lookup directory
151. cell reverse phone number lookup
152. hotmail reverse lookup
153. lookup cell reverse phone number look up
154. reverse lookup by phone number
155. reverse lookup cell phone numbers
156. reverse lookup white pages
157. reverse number lookup cell phone
158. reverse phone number lookups
159. verizon reverse phone number lookup
160. buy cheap reverse cell phone number lookup
161. canada reverse cell phone lookup
162. cell phone free reverse lookup
163. cellular free reverse lookup for phone numbers
164. free reverse cell number lookup
165. free reverse cell phone call lookup
166. free reverse lookup for hotmail
167. lookup free cell phone reverse look up
168. reverse cell phone number lookup sprint
169. tools cell phone number reverse lookup
170. verizon reverse cell phone number lookup
171. alltel reverse lookup
172. cell phone number 21468030630 reverse lookup
173. cell phone number reverse lookup free houston texas
174. cell phone number search of free cell phone reverse lookup
175. cell phone reverse phone lookup
176. cingular cell phone reverse lookup
177. nextel cell phone reverse lookup
178. reverse lookup telephone number
179. unlisted telephone number cell phone reverse lookup
180. cell phone reverse number lookup free
181. find aol email reverse lookup
182. free lookup number phone cell reverse
183. free reverse cell lookup mobile phone number look
184. free reverse cellphone number lookup
185. free reverse fax number lookup
186. nextel cell phone number reverse lookup
187. reverse cell phone 3 lookup 2b free
188. reverse lookup cell phone free
189. reverse sprint cell phone lookup
190. reverse sprint cell phone lookup free
191. voip reverse phone number lookup
192. find cell phone number reverse lookup
193. free cell phone reverse lookups
194. free email reverse lookup
195. free reverse email address lookup
196. nextel reverse cell phone number lookup
197. number lookup reverse cell phone directory
198. reverse number lookup free
199. reverse phone number lookup for cell phone
200. reverse phone number lookup fpr cell phone
201. alltel cell phone reverse lookup
202. cell cricket lookup phone reverse
203. cell lookup number number phone reverse
204. cell lookup number numbers phone reverse
205. email address search reverse lookup
206. free cell phone number reverse cell phone numbers lookup
207. free reverse cell phone number lookup page 2
208. international reverse lookup
209. reverse adress lookup
210. reverse cell phone number reverse phone lookup
211. reverse email lookup free
212. reverse lookup by cell phone number
213. reverse lookup for cell phone number
214. reverse number lookup for cell phone
215. cell lookup number phone phone reverse
216. cell phone reverse lookup unpublished number
217. cingular reverse cell phone lookup
218. free email address reverse lookup
219. free reverse lookup cell phone number searches
220. free reverse lookup cell phones
221. free verizon cell phone number reverse lookup
222. number reverse lookup cell phone numbers
223. reverse fido cell phone lookup
224. reverse lookup email
225. reverse number cell phone lookup
226. reverse telephone lookup by address
227. cell cell free free lookup phone phone reverse
228. cell free lookup number phone reverse search
229. chicago cell phone reverse number lookup
230. directory email lookup reverse
231. email address reverse lookup free
232. free cell phone lookup reverse
233. free reverse cell phone number lookup from verizon
234. free reverse email lookup address
235. free reverse number lookup for cell phone
236. free reverse sprint cell phone number lookup
237. reverse  lookup
238. reverse address lookup free
239. reverse lookup cell phone number cellphone
240. reverse lookup cell phone numbers free
241. reverse lookup verizon
242. reverse phone lookup toll free numbers
243. reverse phone number lookup fpr cell phones
244. reverse phone number lookup uk
245. reverse telephone lookups
246. california reverse address lookup
247. cell for lookup number phone reverse
248. cell free lookup number phone reverse unlisted
249. cell lookup phone reverse
250. cell phone numbers reverse lookup
251. cell phone numbers reverse lookup in colorado
252. cell phone reverse number lookup information
253. cell reverse phone lookup
254. cellular free reverse lookup phone numbers
255. email source address reverse lookup
256. find email address reverse listings finder lookup
257. free cell lookup number phone reverse
258. free cell phone reverse phone number lookup
259. free reverse lookup cell
260. free reverse lookup for cell phone numbers
261. reverse cell phone number lookup htm
262. reverse cell phone number lookup metro pcs for
263. reverse cell phone number lookup search
264. reverse lookup canada cell phone
265. reverse lookup ringers cell phone numbers
266. reverse mobile phone number lookup
267. reverse phone number lookup ontario cell
268. reverse phone number lookup pr cell phones
269. sprint reverse lookup
270. 411 reverse lookup
271. absolutely free reverse cell phone lookup
272. address by email lookup reverse
273. best cell lookup phone reverse
274. canada cell lookup phone reverse
275. cell directory lookup phone reverse
276. cell free lookup phone reverse service
277. cell lookup mobile phone reverse
278. cell lookup phone reverse search
279. cell phone number reverse lookup alltel
280. email search reverse lookup
281. free cell phone directory reverse lookup
282. free cell phone number lookup search reverse search
283. free online reverse phone number lookup
284. free reverse lookup cell cellular phone number
285. lookup reverse cell phone
286. lookup reverse cell phone numbers
287. number lookup cell phone reverse book
288. reverse address lookup canada
289. reverse cell phone number lookup directory
290. reverse cell phone number lookup nh 1
291. reverse cellular phone lookup cell number phone reverse
292. reverse lookup cell phone directory
293. reverse lookup for cell phone numbers
294. reverse lookup on email address
295. reverse phone lookup canada
296. unlisted cell phone reverse lookup
297. verizon cell phone reverse lookup
298. address e email lookup mail reverse
299. at26t cell phone reverse lookup
300. australia email lookup reverse
301. cell lookup nextel phone reverse
302. cell number reverse lookup free
303. cell phone free reverse email lookup
304. cell phone number free reverse lookup
305. cell phone number reverse lookup cheapest
306. cell phone numbers reverse lookup free resources
307. cell phone numbers reverse number lookup
308. cell phone reverse phone number lookup news
309. email address directory reverse lookup
310. email free lookup reverse search
311. email lookup reverse yahoo
312. free cell phone number reverse lookup in canada
313. free cell phone reverse lookup directory
314. free cell phone reverse phone lookup
315. free cell reverse phone lookup
316. free lookup email address reverse search
317. free online reverse cell phone lookup
318. free reverse cell phone number lookup archives
319. free reverse cell phone number lookup sprint spectrum lp
320. free reverse email lookup tx
321. free reverse lookup on cell phone numbers
322. free reverse lookup phone number
323. immediate reverse cell phone lookup
324. ip reverse lookup
325. new unlisted telephone number cell phone reverse lookup
326. people finder free cell phone reverse lookup
327. people finders find reverse cell phone number lookup
328. reverse cell phone directory lookup
329. reverse cell phone lookup california
330. reverse cell phone number 26 land line number lookup
331. reverse cell phone number lookup for free
332. reverse cell phone number lookups
333. reverse email address lookup free
334. reverse hotmail email address lookup
335. reverse lookup cell phone number directory
336. reverse lookup cell phone sprint
337. reverse phone lookup centralia cell
338. reverse phone numbers lookup
339. reverse sprint cell phone number lookup
340. reverse white pages lookup
341. telus reverse lookup
342. a reverse cell phone number lookup
343. address by cell lookup phone reverse
344. address email lookup people reverse search
345. bellsouth cell phone reverse lookup
346. bellsouth reverse cell phone lookup
347. c c reverse cell phone lookup
348. canadian free cell phone reverse lookup
349. cell phone lookup reverse
350. cell phone lookup reverse lookup2c cellular
351. cell phone number reverse lookup for free
352. cell phone number search of free reverse cell phone lookup
353. cell phone number trace cell phone reverse lookup
354. cell phone numbers reverse lookup canada
355. cell phone reverse lookup disconnected telephone number find
356. cell phone reverse lookup find deadbeat husband unpublished
357. cell phone reverse lookup news
358. cell phone reverse phone number lookup archives
359. cheap reverse cell phone lookup
360. completely free reverse cell phone number lookup
361. email addresses reverse lookup all free
362. email addresses reverse lookup uk
363. find free reverse lookup
364. free cell phone numbers lookup reverse cellular
365. free cell phone reverse lookup of free cell phone number
366. free reverse cell phone lookup archives
367. free reverse cell phone number lookup california
368. free reverse verizon cell phone number lookup
369. helen georgia reverse cell phone number lookup
370. lookup free reverse cell phone
371. nyc reverse cell phone lookup
372. orman free reverse cell phone lookup
373. reverse cell lookup cellular phone numbers
374. reverse cell phone number lookup canada
375. reverse cell phone number lookup reverse cell phon
376. reverse cell phone number reverse cellular phone lookup
377. reverse email number lookup
378. reverse lookup and cell phone numbers
379. reverse lookup by phone
380. reverse lookup cell phone directories
381. reverse lookup on cell phone
382. reverse lookup toll free numbers
383. reverse mobile phone lookup
384. reverse phone and email lookup
385. reverse phone directory cell phone number lookup locating
386. reverse phone reverse phone lookup cell phone number trace
387. reverse telephone lookup cell phone
388. sprint cell reverse phone number lookup
389. t mobile reverse cell phone lookup
390. telus cell phone reverse lookup
391. unlisted phone numbers reverse lookup email cellph
392. unlisted phone numbers reverse lookup email cellphone
393. verizon reverse lookup cell phone no
394. verizon reverse number lookup
395. yahoo email address reverse lookup
396. yellow pages reverse number lookup
397. att reverse lookup
398. canada reverse phone lookup
399. cell free lookup phone reverse search
400. cell lookup mobile number phone reverse t
401. cell lookup number phone reverse unlisted
402. cell phone directory reverse lookup
403. cell phone number reverse lookup canada
404. cell phone reverse lookup archives
405. cell phone reverse lookup research
406. cell phone reverse number lookup unlisted numbers free
407. disconnected cell phone reverse cellular phone lookup find
408. email inurl inurl inurl lookup reverse
409. find a free cell phone directory reverse lookup
410. free aol reverse email lookup
411. free cell phone number lookup of free cell phone reverse
412. free cell phone number lookup of free reverse cell phone
413. free cingular reverse cell phone lookup
414. free reverse cell phone number lookup news
415. free reverse cell phone number lookup sprint spe
416. free reverse lookup for cell phones
417. free reverse lookup phone
418. free reverse lookup phone numbers name
419. infospace reverse lookup
420. international reverse phone lookup
421. locate husband by reverse cell phone lookup
422. lookup cell phone number asked answered reverse search
423. nextel reverse number lookup
424. non pub cell phone reverse lookup reverse phone
425. non pub dead beats cell phone reverse lookup cnas
426. omnipoint cell phone reverse lookup
427. perform skiptracing cell phone reverse lookup disconnected
428. qwest cell phone reverse number lookup
429. reverse cell phone cellphone lookup
430. reverse cell phone lookup alltel
431. reverse cell phone lookups
432. reverse cell phone number lookup free of charge
433. reverse cell phone number lookup news
434. reverse cell phone number lookup on unlisted numbers
435. reverse e mail lookupreverse email lookup
436. reverse email lookup australia
437. reverse email lookup for hotmail
438. reverse lookup cell phone canada
439. reverse lookup cellphone
440. reverse lookup for cell phone
441. reverse lookup of phone numbers
442. reverse name lookup
443. reverse phone lookup cell
444. reverse telephone number lookups for free
445. reverse toll free lookup
446. rogers cell phone reverse lookup
447. toll free reverse number lookup
448. uk cell phone reverse lookup
449. unlisted lookup reverse get cell phone numbers
450. unlisted reverse lookup
451. unpublished cell reverse phone lookup
452. www reverse email lookup com
453. yahoo reverse email lookup
454. 411 reverse lookup email addresses
455. account cell info lookup phone reverse
456. address email free lookup reverse
457. ameritech communication lookup mobile reverse
458. canada reverse phone number lookup
459. cell directory free lookup phone reverse
460. cell for free lookup phone reverse
461. cell free lookup phone phone reverse
462. cell lookup phone phone reverse
463. cell phone company reverse lookup
464. cell phone number trace cell phone reverse lookup new cell
465. cell phone numbers reverse lookup free
466. cell phone pouches free reverse cellphone lookup samsung
467. cell phone reverse address lookup
468. cell phone reverse lookup 2b canada
469. cell phone reverse lookup 2c ohio
470. cell phone reverse lookup cell phone
471. cell phone reverse lookup dead beat dead beats
472. cell phone reverse lookup for free
473. cell phone reverse phone number lookup research
474. cellular free lookup numbers phone reverse
475. cheapest reverse cell phone number lookup
476. e-mail reverse lookup
477. email hotmail lookup reverse
478. email lookup reverse
479. find people of free reverse cell phone lookup
480. find unlisted cell phone number reverse phone lookup
481. free and reverse cell phone lookup
482. free cell phone directory reverse adress lookup nu
483. free reverse cell phone lookup t mobile
484. free reverse cell phone number lookup websites
485. free reverse phone number lookup verizon
486. free telephone number reverse lookup
487. free uk reverse email lookup
488. freee reverse cell phone lookup
489. located reverse cell phone lookup
490. lookup free reverse cell phone look up
491. metro pcs cell phone number reverse lookup
492. nextel cell phone reverse number lookup
493. nextel reverse lookup
494. phone hog reverse cell lookup
495. phone number search of free reverse cell phone lookup
496. reverse cell p hone lookup
497. reverse cell phone cellphone number lookup
498. reverse cell phone lookup for rogers at t
499. reverse cell phone lookup in mcallen tx
500. reverse cell phone lookup new york city at26t