Les adresses IP débutant par 121.81.78 sont fournies par K-Opticom Corporation, elles appartiennent au CIDR (Classless Inter-Domain Routing) 121.80.0.0/14, le bloc IP comprant les adresses de 121.80.0.0 à 121.83.255.255). Le numéro de système autonome (ASN) est 17511.
| ASN | 17511 |
| IP commençant par | 121.80.0.0 |
| IP se terminant par | 121.83.255.255 |
| Nom ASN | K-Opticom Corporation |
| CDIR | 121.80.0.0/14 |
| IP numérique | |
| Registe | apnic |
| Dernière mise à jour | 23/07/2017 |

| Code pays | Pays | Région | Ville | Latitude | Longitude | Dernière mise à jour | |
| IP2Location | JP | Japon | - | Amagasaki | 34,733 | 135,4 | 2017-07-22 |
| MaxMind | JP | Japon | - | Takarazuka | 34,8 | 135,35 | 2017-07-22 |
| Whois | JP | - | - | - | 138 | 36 | |
| W3C | - | - | - | - | - | - | - |
| IP | Numerical IP | DNS |
| 121.81.78.0 | 2035371520 | 0 |
| 121.81.78.1 | 2035371521 | 0 |
| 121.81.78.2 | 2035371522 | 0 |
| 121.81.78.3 | 2035371523 | 0 |
| 121.81.78.4 | 2035371524 | 0 |
| 121.81.78.5 | 2035371525 | 0 |
| 121.81.78.6 | 2035371526 | 0 |
| 121.81.78.7 | 2035371527 | 0 |
| 121.81.78.8 | 2035371528 | 0 |
| 121.81.78.9 | 2035371529 | 0 |
| 121.81.78.10 | 2035371530 | 0 |
| 121.81.78.11 | 2035371531 | 0 |
| 121.81.78.12 | 2035371532 | 0 |
| 121.81.78.13 | 2035371533 | 0 |
| 121.81.78.14 | 2035371534 | 0 |
| 121.81.78.15 | 2035371535 | 0 |
| 121.81.78.16 | 2035371536 | 0 |
| 121.81.78.17 | 2035371537 | 0 |
| 121.81.78.18 | 2035371538 | 0 |
| 121.81.78.19 | 2035371539 | 0 |
| 121.81.78.20 | 2035371540 | 0 |
| 121.81.78.21 | 2035371541 | 0 |
| 121.81.78.22 | 2035371542 | 0 |
| 121.81.78.23 | 2035371543 | 0 |
| 121.81.78.24 | 2035371544 | 0 |
| 121.81.78.25 | 2035371545 | 0 |
| 121.81.78.26 | 2035371546 | 0 |
| 121.81.78.27 | 2035371547 | 0 |
| 121.81.78.28 | 2035371548 | 0 |
| 121.81.78.29 | 2035371549 | 0 |
| 121.81.78.30 | 2035371550 | 0 |
| 121.81.78.31 | 2035371551 | 0 |
| 121.81.78.32 | 2035371552 | 0 |
| 121.81.78.33 | 2035371553 | 0 |
| 121.81.78.34 | 2035371554 | 0 |
| 121.81.78.35 | 2035371555 | 0 |
| 121.81.78.36 | 2035371556 | 0 |
| 121.81.78.37 | 2035371557 | 0 |
| 121.81.78.38 | 2035371558 | 0 |
| 121.81.78.39 | 2035371559 | 0 |
| 121.81.78.40 | 2035371560 | 0 |
| 121.81.78.41 | 2035371561 | 0 |
| 121.81.78.42 | 2035371562 | 0 |
| 121.81.78.43 | 2035371563 | 0 |
| 121.81.78.44 | 2035371564 | 0 |
| 121.81.78.45 | 2035371565 | 0 |
| 121.81.78.46 | 2035371566 | 0 |
| 121.81.78.47 | 2035371567 | 0 |
| 121.81.78.48 | 2035371568 | 0 |
| 121.81.78.49 | 2035371569 | 0 |
| 121.81.78.50 | 2035371570 | 0 |
| 121.81.78.51 | 2035371571 | 0 |
| 121.81.78.52 | 2035371572 | 0 |
| 121.81.78.53 | 2035371573 | 0 |
| 121.81.78.54 | 2035371574 | 0 |
| 121.81.78.55 | 2035371575 | 0 |
| 121.81.78.56 | 2035371576 | 0 |
| 121.81.78.57 | 2035371577 | 0 |
| 121.81.78.58 | 2035371578 | 0 |
| 121.81.78.59 | 2035371579 | 0 |
| 121.81.78.60 | 2035371580 | 0 |
| 121.81.78.61 | 2035371581 | 0 |
| 121.81.78.62 | 2035371582 | 0 |
| 121.81.78.63 | 2035371583 | 0 |
| 121.81.78.64 | 2035371584 | 0 |
| 121.81.78.65 | 2035371585 | 0 |
| 121.81.78.66 | 2035371586 | 0 |
| 121.81.78.67 | 2035371587 | 0 |
| 121.81.78.68 | 2035371588 | 0 |
| 121.81.78.69 | 2035371589 | 0 |
| 121.81.78.70 | 2035371590 | 0 |
| 121.81.78.71 | 2035371591 | 0 |
| 121.81.78.72 | 2035371592 | 0 |
| 121.81.78.73 | 2035371593 | 0 |
| 121.81.78.74 | 2035371594 | 0 |
| 121.81.78.75 | 2035371595 | 0 |
| 121.81.78.76 | 2035371596 | 0 |
| 121.81.78.77 | 2035371597 | 0 |
| 121.81.78.78 | 2035371598 | 0 |
| 121.81.78.79 | 2035371599 | 0 |
| 121.81.78.80 | 2035371600 | 0 |
| 121.81.78.81 | 2035371601 | 0 |
| 121.81.78.82 | 2035371602 | 0 |
| 121.81.78.83 | 2035371603 | 0 |
| 121.81.78.84 | 2035371604 | 0 |
| 121.81.78.85 | 2035371605 | 0 |