Ishikawa

Ishikawa is part of the Public Security Section 9. As an extremely skilled hacker who mostly works from the security of a dedicated data centre, he specializes in the gathering of data and resorts to illegal methods if necessary.

Timeline

2027	Arise
2029	Koukaku Kidoutai (1995)
2030	Stand Alone Complex
2032	2nd GIG & Innocence
2034	Solid State Society

Alternate Universes
The anime are spread across three distinct universes.

1. Koukaku Kidoutai and Innocence
2. Stand Alone Complex, 2nd GIG and Solid State Society [Ishikawa]
3. Arise

The differences between the first and the other two universes should be obvious with the example of Aramaki from the timeline alone. While he just started his career in Arise, only two years later he would be an old man looking at retirement. Even older than he is depicted in S.A.C. which according to the timeline comes later.

That Arise and S.A.C. take place in two different universes isn't obvious at first, but becomes clear when examining the timeline in detail. In Arise, Section 9 is formed in 2027, while in S.A.C. it is stated that the unit was established in 2029. It is also shown in S.A.C. that Motoko had the same personality (and perhaps more important the same body) during the Second Vietnam War (2015-2024) and S.A.C. (2030) conflicting with what is seen in Arise (2027).

Source: www.anisearch.com/character/50387