Indonesia–Malaysia border crossings. Illegal immigrants are also known to use such crossings. There are numerous scheduled sea crossings between Indonesia and Malaysia, mostly between ports in the former's island of Sumatra and Peninsula Malaysia. Here is a list of ports (Indonesian port followed by the Malaysian port) where scheduled boat services operate as of April 2008: Sumatra-Peninsula Malaysia North Kalimantan-Sabah Indonesia–Malaysia border The border between the Southeast Asian countries of Indonesia and Malaysia consist of both a land border separating the two countries' territories on the island of Borneo as well as maritime boundaries along the length of the Straits of Malacca,
Brunei–Malaysia border sections which were not covered by these agreements, the two countries agreed that their common border will be delimited based on the watershed principle. In addition, the two countries agreed to push for the joint demarcation and survey of their common border, through the establishment the necessary structures and processes to carry this out. The Memorandum of Understanding on the Process for the Joint Demarcation and Survey of the Land Boundary was signed on 19 March 2012 in Johor Bahru, Malaysia. The MOU, which was signed during the 8th Malaysia–Brunei Darussalam Meeting on the Implementation of the 2009 Exchange of