We give a characterization of distance--preserving subgraphs of Johnsongraphs, i.e. of graphs which are isometrically embeddable into Johnson graphs(the Johnson graph $J(m,\Lambda)$ has the subsets of cardinality $m$ of a set$\Lambda$ as the vertex--set and two such sets $A,B$ are adjacent iff$|A\triangle B|=2$). Our characterization is similar to the characterization ofD. \v{Z}. Djokovi\'c (J. Combin. Th. Ser. B 14 (1973), 263--267) ofdistance--preserving subgraphs of hypercubes and provides an explicitdescription of the wallspace (split system) defining the embedding.
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机译：我们对约翰逊图的距离保持子图进行了刻画，即等距可嵌入约翰逊图的图（约翰逊图$ J（m，\ Lambda）$具有基数$ m $的子集$ \ Lambda $作为顶点集和两个这样的集合$ A，B $相邻，如果iff $ | A \ triangle B | = 2 $。我们的表征类似于D的表征。 \ v {Z}。 Djokovi'c（J. Combin。Th.Ser.B 14（1973），263--267）-保留超立方体的距离的子图，并提供了对定义嵌入的壁面空间（拆分系统）的明确描述。
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